Khanam, Suraiya, et al. “Comparison of Serum Beta Human Chorionic Gonadotropin (S. B-HCG) Level in Preeclamptic and Normal Pregnancy”. Bangladesh Journal of Obstetrics & Gynaecology, vol. 35, no. 1, Mar. 2020, pp. 25-31, doi:10.3329/bjog.v35i1.58260.