KHOIRIA, A.; SASTROWIJOTO, S. A rare cause of esophageal stricture: undifferentiated carcinoma of the lower esophagus. International Journal of Otorhinolaryngology and Head and Neck Surgery, [S. l.], v. 9, n. 2, p. 189–193, 2023. DOI: 10.18203/issn.2454-5929.ijohns20230107. Disponível em: https://www.ijorl.com/index.php/ijorl/article/view/3810. Acesso em: 2 feb. 2026.