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
Mucosal disease was first recognized in Iowa as an apparently new disease entity in cattle in January of 1951. The following inquiry is often made: Is the incidence of mucosal disease in cattle increasing in Iowa? It is difficult to determine accurately the incidence of any disease in farm animals.
Ramsey, F. K.; Chivers, W. H.; Trapp, A. L.; and Whiteman, C. E.
"Incidence and Mortality of Mucosal Disease in Iowa,"
Iowa State University Veterinarian: Vol. 20
, Article 7.
Available at: http://lib.dr.iastate.edu/iowastate_veterinarian/vol20/iss2/7