Bound sets for a class of \(\varphi \)-Laplacian operators (Q2042685)

The authors provide an extension of the Hartman-Knobloch theorem for periodic solutions of vector differential systems to a general class of \(\phi\)-Laplacian differential operators. Their main tool is a variant of the Manásevich-Mawhin continuation theorem developed for this class of operator equations, together with the theory of bound sets. They also extend a classical theorem by Reissig for scalar periodically perturbed Liénard equations.