3Vivrette S.The endocrinology of parturition in the mare. Vet Clin North Am Equine Fract, 1994; 10( 1 ) : 1.
4Norman M. Ekman G, Malrnstrom A. changed proteoglycan metabolism in human cervix immediately after spontaneous veginal delivery. Obstet Gynecol, 1993;81(2):217.
