title: Population studies on the infective stage of some nematode parasites of sheep. I. The frequency distribution of strongyloid infective larvae in random samples of pasture.
mesh_terms: D000383:Agriculture; D000818:Animals; D012756:Sheep; D012757:Sheep Diseases / Q000453:epidemiology*; D013223:Statistics as Topic; D014251:Trichostrongyloidea