@article{VMUMM_1998_4_a7,
     author = {A. A. Shkalikov},
     title = {How should the {Orr{\textendash}Sommerfeld} operator be defined?},
     journal = {Vestnik Moskovskogo universiteta. Matematika, mehanika},
     pages = {36--43},
     year = {1998},
     number = {4},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/VMUMM_1998_4_a7/}
}