1. The growth of populations;Pearl;Q. Rev. Biol.,1927
2. Notice sur la loi que la population suit dans son accroissement;Verhulst;Corr. Math. Phys. Publ. Part A. Quetelet. T.,1838
3. Über Geschwindigkeit und Grösse der Hefevermerhrung in Würze;Carlson;Biochem. Ztschr.,1913
4. Ecology: The Experimental Analysis of Distribution and Abundance;Krebs,1978
5. S.H. Strogatz, Nonlinear Dynamics and Chaos, Perseus Books, Reading, MA, 1994, pp. 19–20.