Alwes Chester. A History of Western Choral Music
ML 1500 .A46 2014, vols. 1 & 2
DeQadros, André, ed. The Cambridge Companion to Choral Music
ML1500 .C36 2012
Geisler, Ursula. Choral Singing: Histories and Practices
ML 1500 .C48 2014
Karna, Duane, ed. The Use of the International Phonetic Alphabet in the Choral Rehearsal
MT875 .U74 2012
Sharp, Avery T. Choral Music: A Research and Information Guide, 2nd ed.
Reference ML128 .C48 S53 2011
Tarling, Nicholas. Choral Masterpieces: Major and Minor
ML 1500 .T37 2014
Unger, Melvin. Historical Dictionary of Choral Music
Reference ML 102 .V6 U54 2010
For more books on choral music, search for keywords or composers in OneSearch and then limit to Book / ebook as "Content Type" and select Library Catalog Under "Refine Your Search:"
The library location is "Music Collection" for print resources.
Worldcat is an online resource for finding all kinds of items in other libraries. It can tell you which other libraries own what you need, and if you are a member of the Ball State community you can use Worldcat's item listings to go directly to an Interlibrary Loan request.
There are two versions:
http://www.worldcat.org is a free version, with fewer options than the subscription version linked on the Libraries' home page. Its main advantage: it lists libraries that own the item in order by distance from your zip code.
The subscription version requires a Ball State log-in from off-campus. (http://www.bsu.edu/library >> worldcat)
Advanced Search is the default. You can specify the format, dates, language, etc.