1. Sexual selection and polymorphism;Charlesworth;Amer. Natur,1975
2. Assortative mating and reciprocal difference in the Blue-Snow Goose complex;Cooch;Nature (London),1959
3. The adaptive significance of pair formation types in weaver birds;Crook,1962
4. The evolution of social organisation and visual communication in the weaver birds (Ploceinae);Crook;Behav. Suppl,1964
5. The adaptive significance of avian social organizations;Crook,1965