Superharmonic extension and harmonic approximation
Annales de l'Institut Fourier, Volume 44 (1994) no. 1, p. 65-91

Let Ω be an open set in n and E be a subset of Ω. We characterize those pairs (Ω,E) which permit the extension of superharmonic functions from E to Ω, or the approximation of functions on E by harmonic functions on Ω.

Soient Ω un ouvert de n et E une partie de Ω. Nous caractérisons les paires (Ω,E) qui nous permettent d’étendre les fonctions surharmoniques de E à Ω, ou d’approcher les fonctions sur E par les fonctions harmoniques sur Ω.

@article{AIF_1994__44_1_65_0,
     author = {Gardiner, Stephen J.},
     title = {Superharmonic extension and harmonic approximation},
     journal = {Annales de l'Institut Fourier},
     publisher = {Association des Annales de l'institut Fourier},
     volume = {44},
     number = {1},
     year = {1994},
     pages = {65-91},
     doi = {10.5802/aif.1389},
     zbl = {0795.31004},
     mrnumber = {95a:31006},
     language = {en},
     url = {http://www.numdam.org/item/AIF_1994__44_1_65_0}
}
Gardiner, Stephen J. Superharmonic extension and harmonic approximation. Annales de l'Institut Fourier, Volume 44 (1994) no. 1, pp. 65-91. doi : 10.5802/aif.1389. http://www.numdam.org/item/AIF_1994__44_1_65_0/

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