R. Kumar Gupta, P. Singh, R. Kumari, B. Langer, P. Sharma, and R. Gupta, “Assessment of knowledge and attitude about emergency contraception: a cross sectional study among medical students in North India”, Int J Reprod Contracept Obstet Gynecol, vol. 6, no. 9, pp. 4042–4047, Aug. 2017.