Byl, J. (2008). Having a ball: Stability ball games. Human Kinetics.
Chicago Style aipamenaByl, John. Having a Ball: Stability Ball Games. Champaign, Illinois: Human Kinetics, 2008.
MLA aipamenaByl, John. Having a Ball: Stability Ball Games. Human Kinetics, 2008.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.