World Association for the Advancement of Veterinary Parasitology (W.A.A.V.P.) methods for the detection of anthelmintic resistance in nematodes of veterinary importance - Coles, GC; Bauer, C; Borgsteede, FHM; Geerts, S; Klei, S; Taylor, MA; Waller, PJ (Vet Parasitol, 1992)