APA

Graham D. L., Calnek B. W., .Papovavirus infection in hand-fed parrots: virus isolation and pathology. : .

Chicago

Graham David L, Calnek Bruce W, .Papovavirus infection in hand-fed parrots: virus isolation and pathology. : .

Harvard

Graham D. L., Calnek B. W., .Papovavirus infection in hand-fed parrots: virus isolation and pathology. : .

MLA

Graham David L, Calnek Bruce W, .: . .