@article{01740989,
title = {Strongly elliptic operators for a plane wave diffraction problem in Bessel potential spaces.},
journal = {JIPAM. Journal of Inequalities in Pure \& Applied Mathematics [electronic only]},
volume = {3},
year = {2002},
zbl = {1003.78004},
language = {en},
url = {http://dml.mathdoc.fr/item/01740989}
}
Castro, L.P. Strongly elliptic operators for a plane wave diffraction problem in Bessel potential spaces.. JIPAM. Journal of Inequalities in Pure & Applied Mathematics [electronic only], Tome 3 (2002) . http://gdmltest.u-ga.fr/item/01740989/