1. Premature induction of calving;Noakes,1976
2. Controlled parturition in cattle;Wagner;J. Anim. Sci.,1974
3. Retained placenta;Roberts,1971
4. Retained fetal membranes. The effect on prolificacy of dairy cattle;Erb;J.A.V.M.A.,1958
5. Effects of season and high environmental temperature on fertility in cattle: a review;Vincent;J.A.V.M.A.,1972