It is shown that, under very general hypotheses, the linear elliptic differential system Lu = 0 possesses the Runge property when and only when the Dirichlet problem for the operator (i.e. the generalized biharmonic problem) has only one solution with a finite energy integral.
@article{RLINA_1979_8_66_2_110_0,
author = {Pieranita Castellani Rizzonelli},
title = {Propriet\`a di approssimazione $\mathcal{L}^{2}$ di Runge e problema biarmonico generalizzato},
journal = {Atti della Accademia Nazionale dei Lincei. Classe di Scienze Fisiche, Matematiche e Naturali. Rendiconti},
volume = {66},
year = {1979},
pages = {110-116},
zbl = {0463.35028},
language = {it},
url = {http://dml.mathdoc.fr/item/RLINA_1979_8_66_2_110_0}
}
Castellani Rizzonelli, Pieranita. Proprietà di approssimazione $\mathcal{L}^{2}$ di Runge e problema biarmonico generalizzato. Atti della Accademia Nazionale dei Lincei. Classe di Scienze Fisiche, Matematiche e Naturali. Rendiconti, Tome 66 (1979) pp. 110-116. http://gdmltest.u-ga.fr/item/RLINA_1979_8_66_2_110_0/
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