Criteria for the Individual $C^m$-Approximability of Functions on Compact Subsets of $ {\mathbb R}^N$ by Solutions of Second-Order Homogeneous Elliptic Equations

Criteria for the Individual $C^m$-Approximability of Functions on Compact Subsets of $ {\mathbb R}^N$ by Solutions of Second-Order Homogeneous Elliptic Equations | AMiner