Nichols, D. K., Lamirande, E. W., Pessier, A. P., Longcore, J. E., (2001). Journal of Wildlife Diseases 37(1), 1-11. Wildlife Disease Association, Lawrence, USA. English language
Pessier, A. P., Nichols, D. K., Longcore, J. E., Fuller, M. S., (1999). Journal of Veterinary Diagnostic Investigation 11(2), 194-199. English language