Amstutz, H. E., R. L. Morter, and C. H. Armstrong. “Antimicrobial Resistance of Strains of Pasteurella Hemolytica Isolated from Feedlot Cattle”. The Bovine Practitioner, vol. 1982, no. 17, Nov. 1982, pp. 52-55, doi:10.21423/bovine-vol1982no17p52-55.