1. The influence of fetal genotype upon endometrial cup development and PMSG and progestagen production in equids;Allen W.R.;J. Reprod. Fertility,1975
2. The origin of the equine endometrial cups. I. Production of PMSG by fetal trophoblast cells;Allen W.R.;J. Reprod. Fertility,1972
3. Between-species transfer of horse and donkey embryos: a valuable research tool;Allen W.R.;Equine Vet. J.,1985
4. Extraspecific donkey-in-horse pregnancy as a model of early fetal death;Allen W.R.;J. Reprod. Fertility,1987
5. Immunological aspects of pregnancy in mules;Antczak D.F.;Equine Vet. J.,1985