On a Harnack inequality for the elliptic (p, q)-Laplacian
Yu. A. Alkhutov, Mikhail Dmitriyevich Surnachev · Doklady Mathematics · 2016
A special Harnack inequality is proved for solutions of nonlinear elliptic equations of the p ( x )-Laplacian type with a variable exponent p ( x ) that takes different values on two sides of a hyperplane dividing the domain. Examples are given showing that the classical Harnack inequality does not hold in this case.