1. Berube DE (1972) Behavioral and physiological adaptations in the evolution of foodplant specificity in a species complex of Colias butterflies. Ph D Thesis, Yale University
2. Bush GL (1969) Sympatric host race formation and speciation in frugivorous flies of the genus Rhagoletis (Diptera, Tephritidae). Evolution 23:237?251
3. Bush GL (1973) The mechanism of sympatric host race formation in the true fruit flies (Tephritidae). On: White MJD (ed) Genetic Mechanisms of Speciation in Insects. Reidel Publishing Co., Boston, 3?23
4. California Department of Food and Agriculture (1979) Estimated damage and crop loss caused by insect and mite pests 1977
5. California Department of Food and Agruculture (1978) Estimated damage and crop loss caused by insect and mite pests 1976