1. Bozarth & Chow, Contr. Boyce Thompson Inst. Pl. Res. 23: 301, 1966.
2. Gibbs, Harrison & Woods, Virology 29: 348, 1966.
3. Hagedorn, Layne & Ruppel, Phytopathology 54: 843, 1964.
4. Izadpanah & Shepherd, Virology 28: 463, 1966.
5. Kennedy, Day & Eastop, A conspectus of aphids as vectors of plant viruses, London, Commonwealth Institute of Entomology, 1962.
6. McEwan & Schroeder, Pl. Dis. Reptr 40: 11, 1956.
7. McWhorter & Cook, Pl. Dis. Reptr 42: 51, 1958.
8. Nault, Gyrisco & Rochow, Phytopathology 54: 1269, 1964.
9. Osborn, Phytopathology 25: 160, 1935.
10. Osborn, Phytopathology 28: 923, 1938.
11. Quantz, NachrBl. dt. PflSchutzdienst (Braunschw.), Stuttg. 4: 24, 1952.
12. Ruppel & Hagedorn, Phytopathology 53: 813, 1963.
13. Shepherd, Wakeman & Ghabrial, Virology 35: 255, 1968.
14. Shikata, Maramorosch & Granados, Virology 29: 426, 1966.
15. Shikata & Maramorosch, Virology 30: 439, 1966.
16. Smith, Textbook of Plant Virus Diseases, London, Churchill, 1937.
17. Stubbs, Viruses of the garden pea (Pisum sativum), Ph.D. thesis, Univ. Wisc., 1935.
18. Sylvester, Virology 25: 62, 1965.
19. Sylvester & Richardson, J. econ. Ent. 59: 255, 1966.