Si dà una condizione sufficiente ad assicurare il carattere fortemente oscillatorio dei sistemi ellittici del tipo Con questo risultato si estendono vari criteri noti relativi al caso di una sola equazione.
@article{RLINA_1975_8_59_6_595_0,
author = {Samuel M. Rankin},
title = {Strong oscillation of elliptic systems of second order partial differential equations},
journal = {Atti della Accademia Nazionale dei Lincei. Classe di Scienze Fisiche, Matematiche e Naturali. Rendiconti},
volume = {59},
year = {1975},
pages = {595-602},
zbl = {0352.35012},
mrnumber = {0492761},
language = {en},
url = {http://dml.mathdoc.fr/item/RLINA_1975_8_59_6_595_0}
}
Rankin, Samuel M. Strong oscillation of elliptic systems of second order partial differential equations. Atti della Accademia Nazionale dei Lincei. Classe di Scienze Fisiche, Matematiche e Naturali. Rendiconti, Tome 59 (1975) pp. 595-602. http://gdmltest.u-ga.fr/item/RLINA_1975_8_59_6_595_0/
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