Buchanan J W, Boggs L S, Dewan S, Regan J, Myers N C
Department of Clinical Studies, School of Veterinary Medicine, University of Pennsylvania, Philadelphia 19104, USA.
J Vet Intern Med. 1998 Mar-Apr;12(2):109-15. doi: 10.1111/j.1939-1676.1998.tb02104.x.