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
Two years ago this spring a rather unusual thing occurred involving three thoroughbred mares. These three mares were owned by an Indiana man and were boarded in this locality near Lexington, Ky., to be bred and foal on one particular horse farm. All three were maidens, that is, carrying their first foals, and all fairly good individuals.
Davidson, A. H.
"A Little of the Unusual,"
Iowa State University Veterinarian: Vol. 3
, Article 11.
Available at: http://lib.dr.iastate.edu/iowastate_veterinarian/vol3/iss2/11