Geodesic
Degenerate Cases of Uniform Approximation by Solutions of Systems with Surjective Symbols
Canadian journal of mathematics, Tome 45 (1993) no. 4, pp. 740-757

Voir la notice de l'article provenant de la source Cambridge University Press

We prove that each (vector-valued) function in Sobolev space on a compact set K, which in the interior K 0 of K satisfies a system of differential equations, can be approximated by solutions in a neighbourhood of K plus sums of potentials of measures supported on the boundary of K. We discuss the particular case where, for all compact sets K, one can dispense with potentials in such approximations
DOI : 10.4153/CJM-1993-042-5
Mots-clés : 35A35, 31B35, elliptic systems, surjective symbols, uniform approximation 
Gauthier, P. M.; Tarkhanov, N. N. Degenerate Cases of Uniform Approximation by Solutions of Systems with Surjective Symbols. Canadian journal of mathematics, Tome 45 (1993) no. 4, pp. 740-757. doi: 10.4153/CJM-1993-042-5
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