Sturm comparison theorem of solution for second order nonlinear differential equations (Q1765863)

Using some differential inequalities obtained in this paper, the authors present several results of comparison character, in which the oscillation of the nonlinear differential equation \[ [p_2(t)y'(t)]'+r_2(t)y'(t)+q_2(t)f(y(t))=0 \] is derived from the same property of the linear differential equation \([p_1(t)x'(t)]'+r_1(t)x'(t)+q_1(t)x(t)=0\). Unfortunately, neither examples for illustration of obtained results nor a comparison with other known results are in the paper.