@article{AA_1993_5_2_a7,
     author = {S. A. Nazarov and M. V. Olyushin},
     title = {Perturbation of the eigenvalues of the {Neumann} problem due to the variation of the domain boundary},
     journal = {Algebra i analiz},
     pages = {169--188},
     publisher = {mathdoc},
     volume = {5},
     number = {2},
     year = {1993},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/AA_1993_5_2_a7/}
}