Gudger, E.W. (January 1930). “On the alleged penetration of the human urethra by an Amazonian catfish called candiru with a review of the allied habits of other members of the family pygidiidae”. The American Journal of Surgery (Elsevier Inc.) 8 (1): 170–188. doi:10.1016/S0002-9610(30)90912-9. ISSN0002-9610.
Gudger, E.W. (January 1930). “On the alleged penetration of the human urethra by an Amazonian catfish called candiru with a review of the allied habits of other members of the family pygidiidae”. The American Journal of Surgery (Elsevier Inc.) 8 (1): 170–188. doi:10.1016/S0002-9610(30)90912-9. ISSN0002-9610.