Given Petrovsky 's expertise in differential equations, the topology of algebraic curves and surfaces and mathematical physics, it is not difficult to see his influence on the direction that Oleinik's work would take.
Given Petrovsky 's kadalubhasaan sa kaugalian equation, ang topology ng algebraic kurva at ibabaw at matematika physics, ito ay hindi na mahirap na makita ang kanyang impluwensiya sa direksyon na Oleinik ng trabaho ay tumagal.