Bhalla, S., S. G. Bhatti, and S. Devgan. “Obstetric and Perinatal Outcome of Twin Pregnancy: A Prospective Study in a Tertiary Care Hospital in North India”. International Journal of Reproduction, Contraception, Obstetrics and Gynecology, vol. 7, no. 6, May 2018, pp. 2455-61, doi:10.18203/2320-1770.ijrcog20182368.