@article{FAA_1971_5_1_a8,
     author = {V. V. Grushin},
     title = {On the proof of the discreteness of the spectrum of one class of differential operators in $\mathbb{R}^n$},
     journal = {Funkcionalʹnyj analiz i ego prilo\v{z}eni\^a},
     pages = {71--72},
     publisher = {mathdoc},
     volume = {5},
     number = {1},
     year = {1971},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/FAA_1971_5_1_a8/}
}