Onset and characteristics of the midcycle surge in bioactive and immunoactive luteinizing hormone secretion in normal women: influence of physiological variations in periovulatory ovarian steroid hormone secretion. - Fritz,M.A.; McLachlan,R.I.; Cohen,N.L.; Dahl,K.D.; Bremmer,W.J.; Soules,M.R. (J Clin Endocrinol Metab, 1992)