Knights C B, Lee K, Rycroft A N, Patterson-Kane J C, Baines S J
Department of Veterinary Clinical Sciences, Royal Veterinary College, Hawkshead Lane, North Mymms, Hertfordshire AL9 7TA, UK.
Vet Rec. 2008 Mar 29;162(13):415-6. doi: 10.1136/vr.162.13.415.