1. 1) Appel, M. J. G. 1988. Does canine coronavirus augment the effects of subsequent parvovirus infection? Vet. Med. 83: 360-366.
2. 2) Appel, M. J. G., Cooper, B. J., Greisen, H. and Carmichael, L. E. 1978. Status report: Canine viral enteritis. J. Am. Vet. Med. Assoc. 173: 1516-1518.
3. 3) Appel, M. J. G., Cooper, B. J., Greisen, H., Scott, F. and Carmichael, L. E. 1979. Canine viral enteritis. I. Status report on corona- and parvo-like viral enteritides. Cornell Vet. 69: 123-133.
4. 4) Appel, M., Meunier, P., Pollock, R., Greisen, H., Carmichael, L. and Glickman L. 1980. Canine viral enteritis. Canine Prac. 7: 22-36.
5. 5) Barlough, J. E., Jacobson, R. H. and Scott F. W. 1983. Macrotiter assay for coronavirus-neutralizing activity in cats using a canine continuous cell line (A-72). Lab. Anim. Sci. 33: 567-570.