@article{DAN_1993_332_4_a9,
     author = {N. S. Nadirashvili},
     title = {An isoperimetric inequality for the main frequency of a clamped plate},
     journal = {Doklady Akademii Nauk},
     pages = {436--439},
     publisher = {mathdoc},
     volume = {332},
     number = {4},
     year = {1993},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1993_332_4_a9/}
}