Carole, Assontsa Kafack, et al. “Comparative Effect of Calcium Supplementation on the Incidence of Pre-Eclampsia and Eclampsia Among Primigravid Women”. Clinical Journal of Obstetrics and Gynecology, vol. 2, no. 2, Dec. 2019, pp. 145-9, doi:10.29328/journal.cjog.1001038.