1. Baker, J. A., C. J. York, J. H. Gillespie, andG. B. Mitchell: Virus diarrhea in cattle. Amer. J. vet. Res.57, 525?531 (1954).
2. Bodon, L.: Contamination of various hog cholera virus strains with adenoviruses or virus diarrhoea virus. Acta vet. Acad. Sci. hung.15, 471?472 (1965).
3. Cusumano, C. L.: Density gradient centrifugation studies of rubella virus. Proc. Soc. exp. Biol. (N.Y.)122, 461?465 (1966).
4. Gillespie, J. H., J. A. Baker, andK. McEntee: A cytopathogenic strain of viras diarrhea virus. Cornell Vet.50, 73?79 (1960).
5. Gutekunst, D. E., andW. A. Malmquist: Separation of a soluble antigen and infectious particles of bovine viral diarrhea viruses and their relationship to hog cholera. Canad. J. comp. Med.27, 121?123 (1963).