1. Alfieri, S. A., and R. F. Stouffer: Evidence of immunity from virus S in the potato variety Saco. Amer. Potato J. 34, 55–56 (1957).
2. Bagnall, R. H.: Saco potato infected with potato virus S by grafting. Phytopathology 55, 707 (1965).
3. Bagnall, R. H., R. H. Larson, and J. C. Walker: Potato viruses M, S and X in relation to interveinal mosaic of the Irish Cobbler variety. Wisconsin Agric. Experim. Stat. Res. Bull. 198, 1–45 (1956).
4. Bagnall, R. H., C. Wetter, and R. H. Larson: Differential host and serological relationships of potato virus M, potato virus S and carnation latent virus. Phytopathology 49, 435–442 (1959).
5. Bagnall, R. H., and D. A. Young: Inheritance of immunity to virus S in the potato. Amer. Potato J. 36, 292 (1959).