Josef Hofbauer and Joseph Wai-Hung So:

Multiple limit cycles for predator-prey models

Mathematical Biosciences 99 (1990), 71-75.

Abstract. We construct a Gause type predator-prey model with concave prey isocline and (at least) two limit cycles. This serves as a counterexample to a global stability criterion of Hsu (Math. Biosci. 1978).

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