Njue AI, Prichard RK. Efficacy of ivermectin in calves against a resistant Cooperia oncophora field isolate. Parasitol Res. 2004 Aug 1;93(5):419-22.
Morant SV, Gnanasakthy A. A new approach to the mathematical formulation of lactation curves. Anim Prod Sci. 1989 Oct;49(2):151-62.