@article{FAA_1968_2_2_a6, author = {V. P. Maslov}, title = {A criterion for discreteness of the spectrum of a {Sturm--Liouville} equation with an operator coefficient (apropos the article by {B.~M.~Levitan} and {G.~A.~Suvorchenkova)}}, journal = {Funkcionalʹnyj analiz i ego prilo\v{z}eni\^a}, pages = {63--67}, publisher = {mathdoc}, volume = {2}, number = {2}, year = {1968}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/FAA_1968_2_2_a6/} }