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 the morning of June 14, 1941, Dr. L. E. Smith of Jefferson, Iowa, was called in consultation by a neighboring veterinarian to observe a rather unusual skin condition in a group of horses. The client had lost one animal, had four more with lesions, and had two animals that were not affected,
Karber, M. W.
Iowa State University Veterinarian: Vol. 4
, Article 13.
Available at: https://lib.dr.iastate.edu/iowastate_veterinarian/vol4/iss1/13