@article{AA_2004_16_1_a10,
     author = {B.Helffer and D. Robert and X. P. Wang},
     title = {Semiclassical analysis of a~nonlinear eigenvalue problem and nonanalytic hypoellipticity},
     journal = {Algebra i analiz},
     pages = {320--334},
     publisher = {mathdoc},
     volume = {16},
     number = {1},
     year = {2004},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/AA_2004_16_1_a10/}
}