A "matching" method for planar harmonic functions is exhibited, using an elliptic adjoint equation .
@article{BUMI_2009_9_2_1_239_0,
author = {Orazio Arena},
title = {A Gluing Theorem for the Elliptic Adjoint Operator $L^{\star}$ in the Plane},
journal = {Bollettino dell'Unione Matematica Italiana},
volume = {2},
year = {2009},
pages = {239-244},
zbl = {1176.31001},
mrnumber = {2493653},
language = {en},
url = {http://dml.mathdoc.fr/item/BUMI_2009_9_2_1_239_0}
}
Arena, Orazio. A Gluing Theorem for the Elliptic Adjoint Operator $L^{\star}$ in the Plane. Bollettino dell'Unione Matematica Italiana, Tome 2 (2009) pp. 239-244. http://gdmltest.u-ga.fr/item/BUMI_2009_9_2_1_239_0/
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