@article{02064649,
title = {On Fourier series in eigenfunctions of elliptic boundary value problems.},
journal = {Georgian Mathematical Journal},
volume = {10},
year = {2003},
pages = {401-410},
zbl = {1050.35054},
language = {en},
url = {http://dml.mathdoc.fr/item/02064649}
}
Agranovich, M.S.; Amosov, B.A. On Fourier series in eigenfunctions of elliptic boundary value problems.. Georgian Mathematical Journal, Tome 10 (2003) pp. 401-410. http://gdmltest.u-ga.fr/item/02064649/