Kara, Ozgur, Gulenay Gencosmanoglu Turkmen, Halil Korkut Daglar, Cem Yasar Sanhal, Bergen Laleli Koc, Aykan Yucel, and Dilek Sahin. 2021. “A Day 1 HCG Can Differentiate Non-Viable Intrauterine Pregnancy and Ectopic Pregnancy Following Endometrial Curettage ”. Annals of Medical Research 27 (5): 1422-27. http://www.annalsmedres.org/index.php/aomr/article/view/765.