Armand Ugon, Alfredo, et al. “Intestinal ,occlusion by Alimentary Foreign bodies.: Simple and Combined-Mechanism Obstruction”. Cirugía Del Uruguay, vol. 46, no. 4, Feb. 1976, pp. 271-4, https://replica-revista.scu.org.uy/index.php/cir_urug/article/view/2785.