Schiffer, J. Julkaisussa New Studies in Athletics (2004) “...educational training...”
Schiffer, J. Julkaisussa New Studies in Athletics (2000) “...educational training...”
Schiffer, J. Julkaisussa New Studies in Athletics (1998) “...educational training...”
Schiffer, J. Julkaisussa New Studies in Athletics (1997) “...educational training...”