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
Neoplasms of the mammary glands are quite common in older female dogs. However, they are rarely permitted to reach the size noted in the present case.
Browne, J. G. and Ramsey, F. K.
"Mixed Mammary Gland Tumor Studies in an Aged Dog,"
Iowa State University Veterinarian: Vol. 22
, Article 4.
Available at: http://lib.dr.iastate.edu/iowastate_veterinarian/vol22/iss3/4