0-87364-704-1. John Plaster (2006). The Ultimate Sniper: An Advanced TrainingManual For Military And Police Snipers. Paladin Press. pp. 5. ISBN ,0-87364-704-1
University Press. 1990. ISBN 0-300-04536-0. (英文) Karpinski, Gary S. Manual for Ear Training and Sight Singing. Norton. 2007. ISBN 978-0-393-97663-2. (英文) Karpinski