1. Developmental horizons and measurements useful for age determinations of equine embryos and fetuses;Bergin,1967
2. Development of horse embryos up to twenty-two days after ovulation: Observation on fresh specimens;Betteridge;J Anat,1982
3. Ultrasound: An aid for pregnancy detection in the mare;Burns,1986
4. Ultrasonic echography in the mare;Chevalier;J Reprod Fert Suppl,1982
5. Summarized observation on the ultrasonic detection of pregnancy and foetal life in the mare;Fraser;Vet Rec,1973