Abstract
The Sharpe–Lotka–McKendrick (or von Foerster) equations for an agestructured population, with a nonlinear term to represent overcrowding or competition for resources, are considered. The model is extended to include a growth term, allowing the population to be structured by size or weight rather than age, and a general solution is presented. Various examples are then considered, including the case of cell growth where cells divide at a given size.
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2000 Mathematics Subject Classification:
primary 37N25; secondary 92D25

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MathSciNet:
MR2376??? 
^{†}indicates author for correspondence 
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