Boutsis, C.; Ellis, Harold (January 1974). "The ivalon-sponge-wrap operation for rectal prolapse: An experience with 26 patients". Diseases of the Colon & Rectum. 17 (1): 21–37. doi:10.1007/BF02587532.
Banov, L. Jr. (December 1965). "The Chester Beatty Medical Papyrus: the earliest known treatise completely devoted to anorectal diseases". Surgery. 58 (6): 1037–1043. PMID5322341. From the title (text not accessed).