Oscillatory behavior of the second order noncanonical differential equations

Establishing monotonical properties of nonoscillatory solutions we introduce new oscillatory criteria for the second order noncanonical differential equation with delay/advanced argument \begin{equation*} (r(t)y'(t))'+p(t)y(\tau(t))=0. \end{equation*} Our oscillatory results essentially extend the earlier ones. The progress is illustrated via Euler differential equation