Herrera, Enrique, Eduardo Otero, Luis Carlos Hincapié, Rafael Camacho, Gustavo Gómez, Carlos Humberto Quintero, Célico Guzmán, and Paola Otero. “Heterotopic Pregnancy. Presentation of Four Cases”. Colombia Medica 42, no. 4 (November 24, 2011): 518–522. Accessed April 25, 2024. https://colombiamedica.univalle.edu.co/index.php/comedica/article/view/953.