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On the oscillation of certain functional differential equations via comparison methods. (English) Zbl 1057.34072
Several oscillation criteria for functional-differential equations of the form $$\frac{d}{dt}\left( \left[ \frac{1}{a_{n-1}(t)}\frac{d}{dt} \frac{1}{a_{n-2}(t)}\frac{d}{dt}\dots\frac{1}{a_{1}(t)}\frac{d}{dt}x(t) \right] ^{a}\right) \pm q(t)f(x[g(t)])=0$$ are established.

##### MSC:
 34K11 Oscillation theory of functional-differential equations
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##### References:
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