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
Polioencephalomalacia is an acute or subacute disease of cattle and sheep characterized by bilaterial blindness without visible eye lesions and by other symptoms of a central nervous system disorder. This disease has been called "forage poisoning" in Colorado and "blind staggers" in Wyoming.
Neal, F. C.; Ramsey, F. K.; Preston, Kenneth S.; and Creel, Robert
"Polioencephalomalacia in Iowa Cattle,"
Iowa State University Veterinarian: Vol. 23
, Article 2.
Available at: http://lib.dr.iastate.edu/iowastate_veterinarian/vol23/iss1/2