1. SAS User's guide;Barr,1979
2. Clinical response of dairy cows with ovarian cysts to GnRH;Bierschwal;J. Anim. Sci.,1975
3. DHIA Annual Summary;Bonewitz,1975
4. Estrus in relation to time of administration of prostaglandin F2α to heifers;Britt;J. Dairy Sci.,1978
5. Frequency of ovarian follicular cysts, reasons for culling and fertility in Holstein-Friesian cows given gonadotropin-releasing hormone at two weeks after parturition;Britt;Am. J. Vet. Res.,1977