Witsberger, Tige H.; Villamil, J. Armando; Schultz, Loren G.; Hahn, Allen W.; Cook, James L. (2008-06-15). "Prevalence of and risk factors for hip dysplasia and cranial cruciate ligament deficiency in dogs". Journal of the American Veterinary Medical Association. 232 (12). American Veterinary Medical Association (AVMA): 1818–1824. doi:10.2460/javma.232.12.1818. ISSN0003-1488. PMID18598150.
Witsberger, Tige H.; Villamil, J. Armando; Schultz, Loren G.; Hahn, Allen W.; Cook, James L. (2008-06-15). "Prevalence of and risk factors for hip dysplasia and cranial cruciate ligament deficiency in dogs". Journal of the American Veterinary Medical Association. 232 (12). American Veterinary Medical Association (AVMA): 1818–1824. doi:10.2460/javma.232.12.1818. ISSN0003-1488. PMID18598150.
Witsberger, Tige H.; Villamil, J. Armando; Schultz, Loren G.; Hahn, Allen W.; Cook, James L. (2008-06-15). "Prevalence of and risk factors for hip dysplasia and cranial cruciate ligament deficiency in dogs". Journal of the American Veterinary Medical Association. 232 (12). American Veterinary Medical Association (AVMA): 1818–1824. doi:10.2460/javma.232.12.1818. ISSN0003-1488. PMID18598150.