@article{1103940282,
author = {Hunziker, W. and Pillet, C.-A.},
title = {Degenerate asymptotic perturbation theory},
journal = {Comm. Math. Phys.},
volume = {88},
number = {2},
year = {1983},
pages = { 219-233},
language = {en},
url = {http://dml.mathdoc.fr/item/1103940282}
}
Hunziker, W.; Pillet, C.-A. Degenerate asymptotic perturbation theory. Comm. Math. Phys., Tome 88 (1983) no. 2, pp. 219-233. http://gdmltest.u-ga.fr/item/1103940282/