1. The disadvantage of heterozygotes in a system of two adjacent populations;Bazykin;Genetika,1972
2. Multiple niche polymorphism;Bulmer;Amer. Natur,1972
3. Sufficient conditions for protected polymorphism in a subdivided population;Christiansen;Amer. Natur,1974
4. An Introduction to Population Genetics Theory;Crow,1970
5. On a variational formula for the principal eigenvalue for operators with maximum principle;Donsker,1975