@article{VMUMM_1983_3_a8,
     author = {Yu. V. Egorov and V. A. Kondratiev},
     title = {Estimate of the first eigenvalue of a selfadjoint elliptic operator},
     journal = {Vestnik Moskovskogo universiteta. Matematika, mehanika},
     pages = {46--52},
     publisher = {mathdoc},
     number = {3},
     year = {1983},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/VMUMM_1983_3_a8/}
}