@article{AA_2009_21_2_a6,
     author = {S. A. Nazarov},
     title = {Opening a~gap in the essential spectrum of the elasticity problem in a~periodic semi-layer},
     journal = {Algebra i analiz},
     pages = {166--204},
     publisher = {mathdoc},
     volume = {21},
     number = {2},
     year = {2009},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/AA_2009_21_2_a6/}
}