1. Kanaev, A. J., Lobuncov, K. A., and Naumova, A. M., Rȳb. Khoz., 43, 16 (1967).
2. Schäperclaus, W., in Handbuch der Virusinfektionen bei Tieren, 2, 1067 (VEB Gustav Fischer, Jena, 1969).
3. Kocylowski, B., Antychowicz, J., and Zelazny, J., Riv. Ital. Piscicult. Ittiopatol., 5, 59 (1970).
4. Markiewicz, F., Medycyna Wet., 22, 16 (1966).
5. Kudenkova, R. A., Symposium on Parasites and Diseases of Fish and Aqueous Invertebrates (in Russian), 17 (Moscow, 1966).