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
An eighteen-month-old Boxer female was admitted to Stange Memorial Clinic, September 29, 1953, with the history of having eaten practically no food in two weeks. Examination revealed that the bitch coughed up blood and had a bloody discharge from both the vulva and anus. Palpation revealed what was thought to be an elongated foreign body in the intestine, but the fluoroscope would not reveal the true nature of the object.
Gubser, Robert K.
"Intussusception in a Dog,"
Iowa State University Veterinarian: Vol. 16
, Article 6.
Available at: https://lib.dr.iastate.edu/iowastate_veterinarian/vol16/iss2/6