The Composition Operator on Mixed-Norm Lebesgue Spaces

It is known that the boundedness of the composition operator on Lebesgue spaces is equivalent to the integrability of the volume derivative of the measurable mapping inducing the given operator. In the present paper, we prove a similar result for mixed-norm Lebesgue spaces in the class of mappings preserving the priority of the variables. © 2019, Pleiades Publishing, Ltd.