Chauhan, N., P. Goyal, A. Lal, J. Chhatwal, and S. Shamim. “Cervical Ectopic Pregnancy: Ultrasound Diagnosis and Conservative Management”. International Journal of Reproduction, Contraception, Obstetrics and Gynecology, vol. 5, no. 10, Dec. 2016, pp. 3613-5, doi:10.18203/2320-1770.ijrcog20163456.