Siff, M. C. (2000, 11. April). PNF as a Training System. Zugriff unter http://www.sportsci.com/SPORTSCI/JANUARY/pnf_as_a_training_system.htm
APA (7th ed.) CitationSiff, M. C. (1999). PNF as a Training System.
Chicago Style (17th ed.) CitationSiff, M. C. PNF as a Training System. 1999.
MLA (9th ed.) CitationSiff, M. C. PNF as a Training System. 1999.
Warning: These citations may not always be 100% accurate.