1. Bald, J. G. 1944. Development in differences in yield between F X and virus-X-infected Up-to-Date potatoes. Austral. Council Sci. and Indus. Res. J. 17: 263–273.
2. Bonde, R. and D. Merriam. 1951. Sixty-seventh annual report. Maine Agr. Expt. Sta. Bull. 491.
3. Canada Dept. Agr. 1968. Research Branch Report, 1967, p. 296.
4. Canada Gazette, Part II, Vol. 103, No. 10, May 28, 1969, p. 658–670.
5. Emilsson, B. and N. Gustafsson. 1956. The influence of potato virus X on yield, tuber size and chemical composition of the tubers. Acta Agr. Scand. 6: 369–382.