article 1961 Residues of pelvic inflammatory disease and abnormal uterine bleeding American journal of obstetrics and gynecology ·doi:10.1016/0002-9378(61)90261-7
article 1956 External Endometriosis and Abnormal Uterine Bleeding American journal of obstetrics and gynecology ·doi:10.1016/s0002-9378(16)37524-x