1. W. C. Allee, Animal Aggregation: A Study in General Sociology (Chicago Univ. Press, Chicago, 1931).
2. W. C. Allee, Cooperation among Animals (Henry Shuman, 1951).
3. W. C. Allee, The Social Life of Animals, 2nd ed. (Beacon Press, 1958).
4. A. D. Bazykin and F. S. Berezovskaya, Probl. Ekol. Monitor. Model. Ekosist. 2, 161 (1979).
5. A. D. Bazykin, Nonlinear Dynamics of Interacting Populations (Inst. Comput. Res., Moscow–Izhevsk, 2003) [in Russian].