Chauhan, N., N. Pahuja, and V. Kalra. “Correlation of Vitamin D Levels With Feto-Maternal Outcome”. International Journal of Reproduction, Contraception, Obstetrics and Gynecology, vol. 7, no. 1, Dec. 2017, pp. 137-41, doi:10.18203/2320-1770.ijrcog20175834.