Iowa State University Veterinarian Records, RS 22/6/0/9, University Archives, Special Collections Department, Iowa State University, http://www.add.lib.iastate.edu/spcl/arch/rgrp/22-6-0-9.html
On March 30, 1951 an 8-year-old Boston Terrier male was admitted to Stange Memorial Clinic. The history was one of constant straining. Examination revealed a large swelling surrounding the anus. A catheter was passed up the urethra and into the bladder without difficulty; hence it seemed doubtful if the bladder was contained in the hernial sac. A diagnosis of bilateral perineal hernia was made.
Wales, Kenneth J.
"Bilateral Perineal Hernia,"
Iowa State University Veterinarian: Vol. 14
, Article 9.
Available at: http://lib.dr.iastate.edu/iowastate_veterinarian/vol14/iss1/9