On oscillation of Volterra integral equations and first order functional differential equations (Q749811)

The author gives conditions for the Volterra integral equation \[ x(t)=f(t)-\int^{t}_{0}a(t,s)g(s,x(s))ds,\quad t\geq 0 \] and the functional differential equation \[ x'(t)+\sum^{n}_{i=1}p_ i(t)| x(g_ i(t))|^{\alpha}sgn x(g_ i(t))=q(t)x(t)+r(t),\alpha >0 \] to have oscillatory solutions.