@article{GDZPPN002204010,
title = {Strong ellipticity of boundary integral operators.},
journal = {Journal f\"ur die reine und angewandte Mathematik},
volume = {372},
year = {1986},
pages = {34-63},
zbl = {0628.35027},
url = {http://dml.mathdoc.fr/item/GDZPPN002204010}
}
Costabel, M., Wendland, W.L. Strong ellipticity of boundary integral operators.. Journal für die reine und angewandte Mathematik, Tome 372 (1986) pp. 34-63. http://gdmltest.u-ga.fr/item/GDZPPN002204010/