* "Encyclopædia Britannica Online" 25 August 2005 "Population Ecology" article section on Population Cycles* de Vries, Gerda; Hillen, Thomas; Lewis, Mark; Schonfisch, Birgitt and Muller, Johannes (2006) "A Course in Mathematical Biology" SIAM.
* "Encyclopædia Britannica Online" 25 August 2005 "Population Ecology" article section on Population Cycles==Further reading==* de Vries, Gerda; Hillen, Thomas; Lewis, Mark; Schonfisch, Birgitt and Muller, Johannes (2006) "A Course in Mathematical Biology" SIAM.