1. The Courship Habits of the Great Crested Grebe;Huxley,1914
2. The evolution of behaviour;Maynard Smith;Sci. Am.,1978
3. One answer to the confinement pig problem;Nehring;Int. J. Study Anim. Probl.,1981
4. Dynamics of the evolution of animal conflicts;Zeeman;J. Theor. Biol.,1981