@article{FAA_1985_19_1_a17,
     author = {G. Nenciu},
     title = {Theory of the self-adjoint extensions of symmetric operators with a spectral gap},
     journal = {Funkcionalʹnyj analiz i ego prilo\v{z}eni\^a},
     pages = {81--82},
     publisher = {mathdoc},
     volume = {19},
     number = {1},
     year = {1985},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/FAA_1985_19_1_a17/}
}