van den Broek A H, Huntley J F
Department of Veterinary Clinical Studies, Royal School of Veterinaary Studies, University of Edimburgh, Easter Bush Veterinary Centre, Roslin, Midlothian EH 9RG.
J Comp Pathol. 2003 Feb-Apr;128(2-3):79-91. doi: 10.1053/jcpa.2002.0627.