López-García, Luis J., Algia Ojeda, and Doris H. Toro. “Primary Duodenal Signet Ring Cell Carcinoma Presenting As Gastric Outlet Obstruction”. Puerto Rico Health Sciences Journal 25, no. 4 (June 29, 2009). Accessed December 19, 2025. https://prhsj.rcm.upr.edu/index.php/prhsj/article/view/292.