Hugh-Jones M E, Turnbull P C, Jones M N, Hutson R A, Quinn C P, Kramer J M
Department of Epidemiology and Community Health, School of Veterinary Medicine, Louisiana State University, Baton Rouge 70803.
Vet Rec. 1991 Jun 29;128(26):615-6. doi: 10.1136/vr.128.26.615.