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 September 24th, 1960, a five month old Angus bull was admitted to the Veterinary Clinic with the history of intermittent dyspnea. During the attacks, the calf would hold its head upward until it was in a vertical plane. The calf would frequently seek a corner in the stall and rest its head in this position.
Cusick, William H.
"Fracture of the Tracheal Rings,"
Iowa State University Veterinarian: Vol. 23
, Article 7.
Available at: http://lib.dr.iastate.edu/iowastate_veterinarian/vol23/iss1/7