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 October 26, 1945 a Guernsey cow was presented at the Stange Memorial Clinic with a history of having chewed off a stomach tube and swallowed it. The cow was in excellent spirits and showed no symptomatology relative to the foreign body in the rumen.
Iowa State University Veterinarian: Vol. 8
, Article 10.
Available at: https://lib.dr.iastate.edu/iowastate_veterinarian/vol8/iss2/10