# A regular solution for the mixed problem for the Laplacian in a bounded set of $\R^n$

Hello, I am looking for a regular (namely $C^2$) solution of the Laplacian roblem with mixed boundary conditions (Dirichlet and Neumann). For example on a rectangle, it would be fine. I want the solution to be $C^2$ and Lipschitz with all partial derivatives Lipchitz.

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