Roberts, M. G., and B. T. Grenfell. 1991. The population-dynamics of nematode infections of ruminants –
periodic perturbations as a model for management. Ima J Math Appl Med 8:83-93.
Roberts, M. G., and B. T. Grenfell. 1991. The population-dynamics of nematode infections of ruminants –
periodic perturbations as a model for management. Ima J Math Appl Med 8:83-93.