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Periodic solutions of a delayed, periodic logistic equation. (English) Zbl 1118.34327
Consider the delay differential equation
${dN(t)\over dt}= N(t)[a(t)- b(t) N^p(t-\sigma(t))- c(t) N^q(t-\tau(t))],\tag{$$*$$}$ where $$a$$, $$b$$, $$c$$, $$\tau$$ are continuous $$\omega$$-periodic functions, $$p$$ and $$q$$ are positive constants. The author establishes the existence of a positive $$\omega$$-periodic solution of $$(*)$$ by using Mawhin’s continuation theorem.

##### MSC:
 34K13 Periodic solutions to functional-differential equations 92D25 Population dynamics (general)
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##### References:
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