Sands, W. A., Kimmel, W. L., McNeal, J. R., Ross Murray, S., Stone, M. H. Julkaisussa Journal of Sports Science & Medicine (2012)
Dubravcic-Simunjak, S., Kuipers, H., Moran, J., Pecina, M., Simunjak, B., Ambartsumov, R., Sakai, H., Mitchel, D., Shobe, J. Julkaisussa Journal of Sports Science & Medicine (2008)