In-Depth Read: “Game On” in your Concert Warm-ups!

Hello, all!  It’s been quite a while since my last “5-Minute Read,” and I figured it was high-time to again write about some of my experiences and thoughts in the band world. Thanks for your patience and support!

I’m certain that we’re all into the full swing of our concert band preparations this semester, and we are faced with that constant question: how, what, how long do we warm-up our concert ensembles? The answers to these questions vary greatly depending on each ensemble’s available class time, instrumentation, and ability level.  But one thing is clear: the vast majority of us, director and musician alike, do not look forward to the daily warm-up. In fact, some of us outright dread it. Why? Because concert works are fun, and scales, arpeggios, and chorales aren’t.  That may be an oversimplification and a blanket statement, but I’m willing to stand by it.  For students, daily warm-ups are the bitter medicine they have to endure before they get to enjoy “real” music. This doesn’t make it any fun for the director either!

This problem has all sorts of ramifications.  First, if the warm-up is uninteresting or not engaging to the students, they will certainly not give their best effort.  Secondly, since the warm-up comes at the beginning of class, this lack of energy and effort can “poison the waters” for the remainder of your class time, negatively affecting how your students play throughout all portions of the rehearsal.  So, how do we fight this problem?  The answer is “Game on!”

Game On!

I know it can sound cliché, but applying games, challenges, and competition to your warm-up process can energize your warm-up, your students, and yourself. Here are some techniques you can use to get your student-musicians to bring their best “game” to warm-up!

  • Are you Bored?
    • Here’s the first and most important test: are you, the director, bored during the warm-up? This is the biggest warning sign that you have an ineffective beginning to your rehearsal.  If you ever find yourself bored, then remember this simple rule for yourself and for your students: “If it’s boring it must be simple, and if it’s simple it must be easy, and if it’s easy it must be perfect. And once it’s perfect, let’s make it harder.” Try these tricks below to do just that!
  • Attacks and Releases at Strong Volume
    Long Tones with Breath Releases and Emptying Counts
    • Don’t let your students start rehearsal with an anemic sound and airstream.  Start with playing forte!  Long tones, at full volume, are a great way to get your students lungs moving and resonating their instruments with rich sounds. Make sure they’re emptying their lungs before breaths, forcing them to take full inhalations.
  • Get Them Singing (and buzzing) Loud and Proud!
    • Dialing in pitch, and breaking through your students’ lethargy, can be helped by having them stand up to get the blood flowing.  Have them stand to sing through your chorales.  Not loud and strong?  Stop and start again until you get the effort and volume you want. Have the woodwinds play the chorale while your brass players try to “outbuzz” them in volume.  Tell your woodwinds not to make it easy on those brass!
  • Push Technique to the Limit
    • Scales are more than scales: they’re the first technical challenges are students face.  So don’t let them get comfortable playing them in easy tempos.  Push them to their limits with progressively more challenging speeds on those scales.
  • An example of a leaderboard.

    Appeal to their Competitive Side

    • Have individual students play for the class everyday!  Work your way around the room throughout the week.  Don’t just let your strongest performers be the only one’s that play, but they can certainly use this time to “show off.”  Cultivate a classroom where your strongest performers receive adulations from their peers, while your weakest performers get encouragement and positive reactions to their efforts.
    • With all of the technology at our fingertips weekly recording or SmartMusic assignments of scales, at set tempos, can be used to create a leaderboard of top performers in your class, with rewards and privileges you determine for your top performers. you don’t have to show everyone’s rank, but you can certainly show the top performers! Anything from candy, to gift cards, to bus loading priority can be used to motivate these high achievers.
  • Involve your percussionists!

    Don’t Leave Out Your Percussionists!

    • Don’t let your percussionists just sit there through the warm-up process.  They need to know how to play their scales on the mallets. But beyond scales, what about rudiments?  Rudiments can be played on snare drums, practice pads, and on mallets!  Paradiddles, flam-taps, and more, at faster and more challenging tempos, can be employed during scale warm-ups.
    • As always, make sure you set aside enough time towards the end of warm-ups for your percussionists to prepare all equipment needed for the works you’ll be rehearsing.

We’re never going to enjoy scales, chorales, and long tones as much as playing a great piece of band literature.  But that doesn’t mean we have to make warm-ups such a chore!  Try these techniques with your band today and you’ll find that not only does their sound and technique improve, but you and your students will begin to look forward to warm-ups, and your class time will start out on a much more positive and energetic footing!

In-Depth Read: “The Visual Airstream”

Air.  It’s the fundamental fuel that allows your wind performers to clearly communicate their musical lines to the audience.  Great air flow is needed to produce a quality, characteristic sound. It’s needed to play with great intonation.  Proper presentation of breath control is needed to accurately attack and release notes as an ensemble, and to do so with clear sound and technique.  The airstream is life! And boy are we bad at using it.

We’re not bad at using air because we’re bad people, but because we simply aren’t attuned to the physical processes that our bodies use to control and direct the airstream.  Breathing is completely automatic for us, and we don’t give a single moment’s thought to our breath as we speak.  Because of this automatic nature of breath, we are not normally perceptive of how we are using the lips, teeth, tongue, and throat to control and direct airflow, and this lack of perception bleeds into our wind players’ performance. Throw in the fact that air is invisible, and it becomes a tough proposition to diagnose and improve your students’ airflow issues.  But making the invisible visible can go a long way towards improving airflow! Here’s how.

Use Visual Monitors

Look at the picture in this article, featuring the West Seneca West High School Wind Ensemble in West Seneca, NY, as it demonstrates the following technique.  This works great, especially for brass players.  Have your students take a simple piece of paper and fold it in half (either way will do) and then hold it in front of their faces, about 6 inches in front of the lips.  Simply have them blow a stream of air onto the paper, but tell them that the paper must bend as far from their lips due to the airflow.  This will establish the strength of the wind column they must produce and sustain.  See how much they can make the paper move and how long they can sustain that distance.

Now, have them put their mouthpieces (works for woodwinds too!) to their lips and blow silent air at that piece of paper (no buzzing or vibrating reeds).  See if their papers still move the same distance, or at all.  You and your students be astounded to see that some of them already have a major decline in airflow, and lips and reeds aren’t even in the way yet!

Finally, have your wind players buzz (any pitch will do) and vibrate their reeds through their mouthpieces at their piece of paper.  This will be the most telling moment of all, as you’ll see over half of that paper in front of their faces barely move at all.  You have made their airstream visible and the results will be sobering for your students!

So where is the air going? Why isn’t it getting out of their lungs and through those mouthpieces. The next steps will help you diagnose and improve this issue.

Do It Wrong!

There are three places that the airstream can be impeded:

  1. Lips
  2. Teeth/Jaw
  3. Tongue/Throat

As mentioned earlier, we as humans aren’t very good at being self-aware of what’s happening in these areas.  So help your students learn what it feels like to control and properly use these areas of their wind column by doing things intentionally wrong first!


Let’s start with the lips.  Have your students clamp their lips tightly and try to blow through their mouthpieces at that piece of paper.  While it seems obvious, lips being too tight, especially in the center of your brass players’ embouchures, is a common air impedance for wind performers.  Now that they can feel what it’s like to do it wrong, have them loosen their lips and blow air onto the paper through their mouthpieces.  Not only will their eyes show them the difference as the paper moves a significantly greater distance, but their eyes will be able to tell a change in the sound of the airflow.  Highlight these differences for them.


The teeth/jaw is another common blockage for airflow, so let’s help open it up.  Have your wind players grit their teeth as they blow at their paper monitor.  Again, highlight the sound quality of the airstream as well as the (lack of) movement in the paper. Now have them pretend to chew a big piece of gum their back teeth as they politely keep their mouths closed.  Have them freeze with their jaw open and then blow their air.  Not only will the teeth be out of the way, creating lots more motion in the paper monitor, but once again there will be a marked change in the sound quality of the exhale. Once again, highlight these differences for your students.


This is the most insidious place where air is stopped.  The placement of the tongue in the mouth directly affects how open the throat is to airflow.  Again, we’re not good at knowing where are tongues are inside our mouths at any given moment, so let’s learn what it feels like to have incorrect tongue placement. First, have your students take their left hands and place it around the tops of their throats (see image). Now have them move their tongues backwards and upwards inside their mouths. They’ll be able to fill their throat filling as the tongue expands and blocks the larynx.  Have them hold the tongue in that position as they blow on their paper monitors.  The sound will be hissing and anemic and the paper will not move very much. Now have them do the opposite, moving the tongue forward and down, resting behind the lower front teeth.  With their left hand, they will feel their throats open.  Have them maintain that tongue position as they blow on their paper monitors, and the sight and sound will be very different!

With all of this newfound awareness of their air column, your students will have a far clearer and more powerful wind stream.  Have them apply this newfound knowledge as they buzz their mouthpieces and reeds and then move to their instruments.  The improvement in volume, tone quality, intonation, range, and more will instantly improve your experience and that of your student performers!

Free!: 12 Weeks to a Better Concert Band

Please note that since this news item was released over a year ago, the “Care and Feeding” program has been a huge success and has now gone on sale in my music shop. You can get the item there!

I am pleased and excited to announce the initial availability of my 12-week concert band warm-up and sound development method, Concert Winds Care and Feeding.  Best of all, this initial offering is free! This project draws upon what I have learned and worked with concert bands over the decades, and distills a lot of information and methods into a program of study for high school and collegiate concert bands.  All 12 keys are explored, with rhythm reading, unison chorales, and harmonizations in every key.  The program also provides a curricular framework for assigning homework, and lays out a recommended system of ensemble tuning.

You can download and use this method completely free. For now, think of this as a piece of open source software.  It is provided free for public use, as long as is it is not altered and the composer’s attribution is not changed or removed. What I want to know is: What works? What doesn’t?  Where are there errors?  How can it be adapted to work better?
The score and parts, complete with an introduction and detailed instructions, are downloadable in one large PDF file available at this link.  Please note that this is a large file, so it may take a while to complete the download.
I look forward to hearing the results and your feedback.  Thank you, and happy banding!

In-Depth Read: Timing Isn’t on your Side!

Greetings and happy fall semester to you! By now, I’m certain that you’re well on your way with your school band ensembles, and you’re looking to begin adding more polish for upcoming performances. And if those performances are on a football field, then chances are you are dealing with all sorts of timing issues in your performance.

The task of getting all of our performers’ sounds to reach the audience at the same time, especially when they are spread across a football field, is a daunting one. But with some careful planning, knowledge of acoustics, and the appropriate rehearsal techniques, you can tighten up your band’s timing to create greater impact on audiences and judges alike!

Demonstrate the Speed of Sound

As always, seeing is believing.  You know that sound travels relatively slowly, and you’ve told your students this before.  But take time to demonstrate this fact to your band members!  Take half of your wind players and place them behind the drumline before playing a short show excerpt while listening to the drumline.  Have the other half of the winds stand up front and listen to the fractured result.  When they hear how timing is terribly affected by this situation, then switch those two halves of wind players.  This way, every single one of your wind players knows and believes intrinsically that the geometry of their placement on the field, in relation to the battery, is highly important in their time-keeping responsibilities.

Use a Backfield Metronome

I’m certain that to many of my readers this may seem insultingly simple and obvious.  However, in my experience, I have seen many bands that are reluctant or resistant to utilizing a backfield metronome during rehearsals.  This simply boils down to a puritanical sense of pride: “We ought not have to use a metronome.” Trust me, no one likes listening to or putting up with a metronome. But remember that a metronome is simply a tool to keep you and your band honest about timing.  More importantly, it also trains your performers to always listen back for their timing (more on that below). Also, a metronome is the only guarantee for the success of your auxiliary performers, who’s tosses and other maneuvers are tied strictly to the written tempos.  Finally, one need not simply leave a metronome set to quarter notes throughout a rehearsal to develop timing.  There are all sorts of metronome games you can play to develop your students’ sense of timing and subdivision.

Assign Specific Listening Responsibilities

Once your students understand the effect that the speed of sound has on their ability to play in time on the field, it’s time to give them some simple rules for when they can play with what they hear, and when they must play with what they see from the drum major’s hands. [Please note that I owe much of the following information to the excellent work of Andrew Rogers.  To see his impressive discussion regarding the calculation of listening assignments on the field, then view his website and this video!]

A simple rule you can give your students is the following: “If you can draw a straight line from the drumline, through yourself, to the drum major, then you can listen, not watch.” Just as our front ensemble members listen backwards for their timing, so can your performers in this zone leading directly from the drumline to the drum major. For example, take a look at this spreadsheet (again, adapted from Andrew Rogers’ work).  It shows the safe listening areas in green.  The performers in this area can simply listen to the performers behind them, and those to others behind them, and on and on until reaching the battery. You’ll notice that these areas are in the cone leading from the battery (represented by the “M” for metronome) on the field to the drum major.


Also note that once outside of that cone, there is a narrow area of marginal listening in yellow, proceeding to a red area.  This red area represents those parts of the field who cannot listen to the battery, or they will be behind to the audience’s ears. Here is another image that shows these various listening environments.


Develop the Winds’ Relationship to the Battery

Simply telling the winds to listen to the battery is rarely enough.  You’ve got to tune their ears to those percussion parts so they understand how they fit in.  To do this, take any set of drill that is giving you timing issues.  Have the winds stand in that set and mark time in place, singing their parts, while they listen back to the battery playing.  No drum major or field conductor should be used, and the percussion should tap off to begin the segment. After that, have the winds mark time in place while they play to the percussion parts. Again, no conductor should be used.  Once the winds have learned how to play in time to the percussion parts coming from behind them, then put the chunk of drill on the move, playing and marching. You’ll find that the impact of sound is now lining up much more tightly!

Educate Your Field Conductors

This can all present quite the challenge for our drum majors and field conductors.  In addition to having to provide clear, unchanging tempos, they must do this while ignoring some conflicting sonic information they are getting from the field.  However, with some simple rules of thumb, you can help your drum majors can provide clear information to your field ensemble. Here are some important rules of thumb to remember!

  1. If the battery is behind the winds, then the center drum major should conduct to what they see the battery doing.  Looking at the center snare’s sticks, feet, etc. are all excellent cues for maintaining appropriate tempo.
  2. If the battery is in front of the winds, then the drum major should be conducting ever-so-slightly ahead of what he/she hears from the battery.  This will ensure that the wind performers’ sounds reach the audience at the same time as the battery.
  3. Side-field conductors and drum majors who are conducting to the areas of the field outside the safe listening environment must conduct slightly ahead of the center conductor’s hands in order to ensure that those performers’ sounds reach the audience simultaneously.

Figuring out how far ahead of the drumline a center conductor should be, or how far ahead a side-field conductor should be of the drum major, takes some work.  First, place yourself in the stands to listen to a certain segment of drill where these timing issues are occurring. Secondly, place another staff member or trusted timing listener behind the wind section outside of the safe listening area. Have that listener stay right behind that wind section as they perform a section of the show.  Have the field listener determine if the performers are actually playing in time with what they hear.  If they are, use your ears in the stands to determine how far behind (an 8th note, a 16th note?) that wind section sounds behind the battery. That’s how far ahead of the drum major your side-field conductor must be.

If this seems complicated, it can be.  However, it’s far better to have one side-field conductor in charge of anticipating the beat than two put that responsibility in the hands of 20+ field performers!

Reap the Benefits of Improved Timing

Besides just giving your band’s sound more polish and maturity, improved ensemble timing results in far greater volume and impact.  When all of those sound waves arrive at the audience simultaneously, they add up and amplify to provide an incredible listening experience that gets a visceral response from audiences and judges alike.  As you look for the next level from your marching band leading into the upcoming performances and competitions, try to implement these ideas in your show.  It will yield tremendous results!

Find Important Alto Clarinet Lines and Rewrite Them in Soprano and Bass Clarinet Parts

NOTE: An earlier version of this article was originally published in the February 2013 issue of Alabreve,

As you begin selecting and rehearsing the music for your concert band’s upcoming performance, take a moment to look at your scores.  Was it published in 1980 or earlier? There’s a lot of great older literature out there, in both our school music libraries and within the required lists of repertoire we can play at Festival (Assessment, Contest, whatever you call it in your state). And this literature is wonderful!  But it sometimes contains an easy-to-miss part that can make or break the quality of your band’s performance.  I refer of course, to the fading and forgotten alto clarinet.

At some point in the history of modern wind band instrumentation, the alto clarinet became a four-letter word. Looking back on articles in The Instrumentalist as early as 1947, one finds well-written pleas to bring back the instrument,1 as well as questions of whether it is even necessary in the modern wind band.2  The alto clarinet’s exodus from the wind band happened for a variety of reasons. The early alto clarinets available to bands were of less than desirable quality, with tuning issues and anemic sound. The expense and time of owning and maintaining an alto clarinet was and is beyond practicality for many bands. Finally, in an ensemble where we seem to be eternally seeking a sufficient number of accomplished clarinet performers, dedicating a student to the alto clarinet may prove impossible. While it is true that the latest models of the alto clarinet (as well as the recently revived basset horn) are quality instruments that overcome the earlier weaknesses in tone production and intonation that doomed the instrument, the heart of the matter is that these other practical concerns have chased the alto clarinet from our bands, and modern composers are simply no longer including the instrument in their scores. As a result, one is more likely to see an alto clarinet hanging on a wall as an objet d’art than in the hands of a high school or college band member.

Faced with the reality of a world without alto clarinets in our bands, what do we do when we meet a concert work that calls for the instrument?  This is the much more practical concern that many of us deal with on the podium, especially when we program wind works published prior to 1980.3 Unfortunately, a common response is to treat the alto clarinet and its part as “optional,” something that can be left out whether it’s covered by other voices or not. This often leads to a sound that at best was not the original intent of the composer, and at worst omits important chord tones not covered in any other voice. However, by knowing how to detect these important lines, and with a minimum of rewrites, important alto clarinet parts can be added to your clarinet and bass clarinet performers’ parts. The results are rewarding for conductor, performer, and audience alike.

Rewriting the Part

First of all, let us discuss how to rewrite an alto clarinet part into other clarinet voices. The two considerations one must weigh are range and tessitura. While a soprano or bass clarinet might have the range to play certain excerpts from an alto clarinet part, the tessitura may not match the intended color in the original alto clarinet part. In its lower range, the alto clarinet’s sound is reminiscent of the throaty, woody sound of the bass clarinet, while in its upper range, it more closely resembles the hollow warmth of the chalumeau register of the soprano clarinet. This chart demonstrates the appropriate target areas for rewriting voices within the alto clarinet’s range.


As demonstrated in the chart, the ranges of the bass clarinet and soprano clarinet overlap in multiple areas (green), and both can be used to replace an important alto clarinet part. The part chosen as the target for a rewritten line will depend on the ability of the performer – and therefore the technical difficulty or exposure of the part – and the desired color. The lower range of the soprano clarinet provides a warm, full sound, while the upper clarino registers are clearer and brighter. The bass clarinet is reedier yet warm in the middle register, and becomes increasingly plaintive and sweet in its clarion register. The conductor must evaluate these color changes when choosing which instrument will receive the rewritten alto clarinet part. A mixture of rewrites in the soprano and bass clarinets will often be the result. The orange highlighted areas feature pitches in which particular care should be taken, as these throat tones may prove challenging, especially when weaker players are given the rewritten part. Of course, practical concerns of who is available to perform a rewritten part will need to be considered.  For example, if you only have one bass clarinetist, that performer will be busy with their own important lines, and therefore unable to perform many alto clarinet rewrites).

Score Study

Knowing how to look for important alto clarinet parts during your score study can help pinpoint those times when a rewrite is required. This can be challenging, as a large scale work that includes an alto clarinet part often features such a plethora of staves that a unique alto clarinet line can be visually “lost in the shuffle.” Also, there are many works and sections of works that simply double the alto clarinet with the bass clarinet, predisposing us to ignore this line. Because of these issues, one of the first steps in your score study should be a thorough inspection of the alto clarinet staff. Look for alto clarinet lines that contain chord tones that are not in any other clarinet part, or lines that double another part in octaves. Finally, look at the areas where the alto clarinet part is exposed while doubling another one or two instrumental parts at the same octave. This is an important color shading that should not be treated as optional.

All of the rewrite examples in this article will be taken from Warren Benson’s The Solitary Dancer and Darius Milhaud’s Suite Française. These works were chosen because they are from composers who have contributed multiple and lasting entries to the wind literature, because they are playable by accomplished high school and undergraduate ensembles, and because this author has put the rewrites into performance practice with his own ensembles. The excerpts given as examples are representative, and by no means the only alto clarinet rewrites necessary in the works discussed.

Unique Alto Clarinet Lines

Warren Benson’s The Solitary Dancer features an extremely important alto clarinet voice, creating marvelous open fifths with the bass clarinet, and generating important chord tones not doubled in any other part. The work is truly incomplete without the alto clarinet line. For example, in measures 43-45, a C-minor sonority would be completely absent if not for the alto clarinet’s Eb concert. Designating a third clarinetist to perform this pitch will complete the harmony.


Later, at measure 65, the alto clarinet generates an important open fifth dyad with the bass clarinet part. This open fifth can be rewritten into either a bass clarinet or soprano clarinet part, depending on available performers.


Alto Clarinet Lines that Complete a Clarinet Choir

Even when the alto clarinet’s pitch is found elsewhere, rich clarinet choir writing that is missing one voice simply does not achieve the composer’s intent. For example, the fourth movement of Darius Milhaud’s Suite Française, “Alsace-Lorraine,” features an exposed clarinet choir choir at measure 55. Though the bassoon 1 and clarinets 2 and 3 take turns covering the pitches in the alto clarinet line, the composer’s clear intent on the page is a clarinet choir; the Eb soprano, all three Bb soprano parts, the alto clarinet, and the bass clarinet are all included in this beautiful, exposed moment. The alto clarinet part is too low for a soprano clarinet to cover, so one bass clarinetist must be assigned to play this rewrite.


Alto Clarinet Lines that Create Parallel Octaves

Sometimes the alto clarinet part doubles another line in octaves, and this is an extremely important sonic quality to preserve, as parallel octaves are a distinct color and texture all their own. For example, in the third movement of Milhaud’s Suite Française, “Ile de France,” measure 12 features a jaunty descending line of open fourths and fifths in the clarinet choir. The first soprano clarinet and alto clarinet lines are in parallel octaves. While the alto clarinet’s pitches are covered in other instruments and other octaves, omitting this voice leaves a hole in what would be a solid span of a perfect 15th. Placing one or more of the third clarinetists on the alto clarinet line repairs this gap in the sonority.


Alto Clarinet Lines that Provide Necessary Color in an Exposed Soli Section

Finally, though you may find the alto clarinet part doubled at the same octave in another voice, the missing clarinet color resulting from ignoring this part can negatively affect the tone quality of your ensemble. This is especially true when the alto clarinet part is only doubling one or two other instruments in an exposed line. For example, Milhaud’s Suite Française features gorgeous alto sax lines, especially in the second movement, “Bretagne.” These motives are doubled (not cued) in unison by the alto clarinet. While the alto saxes are indeed covering this part, the alto clarinet softens and warms their timbre. Omitting this clarinet voice leads to a brighter, reedier sound that is simply not up to Milhaud’s original vision. This necessary rewrite is demonstrated in two areas of the second movement – measures 25 and 36. The same motive is stated by the alto saxophones and the alto clarinet at these two measures, though at different pitch centers. Adding a clarinet voice softens and warms the sound of this line.

At measure 25, the soprano clarinet voice is resting and available, and the register provides an excellent match in timbre to the original alto clarinet part. In addition, the bass clarinet is occupied with a low E concert.


At 36, the motive is stated up a fifth. At this time, the bass clarinet is available to perform a rewrite, and the soprano clarinet would be trapped in a mire of throat tones that would not lead to a desirable sound. Placing the motive into the bass clarinet is more practical, and generates a wonderfully sweet and plaintive sound.


I know this was a lot to read about an instrument we so rarely consider these days.  But if you’re playing any of that pre-1980 literature, including the two pieces mentioned in this article, I promise it’s worth you time to look for the alto clarinet part! While it is highly likely that the alto clarinet will never permanently return to most of our bands, it is important that we not ignore the scoring for this important voice in the earlier wind band literature. As with any other instrument in the ensemble, it was and is an important timbre, and we can still provide this line through other clarinet voices. Taking a moment to scan your score for these important alto clarinet lines, and then rewriting those lines that fall into the categories listed above, will yield a significant and audible improvement  in your ensemble’s performance.

1 Sawhill, Clarence E. WOODWIND: Problem of the Alto Clarinet, the.” The Instrumentalist, 47, 1947. 8.
2 Rohner, Traugott. WOODWIND: Shall we Eliminate the Alto Clarinet?” The Instrumentalist, 47, 1947. 30.
3 Mark Wolbers, “Alto Clarinet: The Endangered Species of the American Band,” paper presented at Annual Meeting of the College Band Directors National Association, University of Washington, Seattle, December 23-26, 2011), PDF file, (accessed December 28, 2011).