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
The possibility of foreign bodies in the intestinal tract should be a consideration in dogs exhibiting persistent emesis. Younger dogs are more likely to ingest foreign objects due to their playful and curious attitude. The object may remain in the stomach and cause varied symptoms depending upon the degree of irritation to the gastric mucosa and the size of the object.
"Intestinal Obstruction of the Canine,"
Iowa State University Veterinarian: Vol. 19
, Article 10.
Available at: http://lib.dr.iastate.edu/iowastate_veterinarian/vol19/iss2/10