@article{MZM_1990_47_3_a8,
     author = {V. Yu. Ovsienko},
     title = {Self-adjoint differential operators and curves on {a~Lagrangian} {Grassmannian,} subject to a~train},
     journal = {Matemati\v{c}eskie zametki},
     pages = {65--73},
     publisher = {mathdoc},
     volume = {47},
     number = {3},
     year = {1990},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_1990_47_3_a8/}
}