The Brenner-Hochster-Koll\'ar and Whitney Problems for Vector-valued   Functions and Jets
  In this paper, we give analytic methods for finding m (and m+\omega) times continuously differentiable solutions of a finite system of linear equations. Along the way, we also solve a generalized Whitney problem for vector-valued functions and jets. 
Charles L. Fefferman, Garving K. Luli
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