[1] BRAUN, M., Differential Equations and Their Applications: An Introduction to Applied Mathematics, 4ª ed., Springer-Verlag, New York, 1993

[2] D'ANCONA, U., The Struggle for Existence, E. J. Brill, Leiden, 1954

[3] GOEL, N., S. MANTRA e E. MONTROL, On the Volterra and Other Nonlinear Models of Interacting Populations, in Reviews of Modern Physics 43, 1971, pp. 231 - 276

[4] HIRSCH, M. e S. SMALE, Differential Equations, Dynamical Systems, and Linear Algebra, Academic Press, New York, 1974