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3. Effects of exogenous progestogens on reproductive phenomena in mares;Loy;J Anim Sci,1966
4. Progesterone concentrations in the peripheral plasma of the mare during the oestrous cycle;Smith;J Endocrinol,1970
5. Changes in peripheral plasma progesterone throughout the oestrous cycle of the pony mare;Sharp;J Reprod Fertil,1973