@article{FAA_1989_23_1_a8,
     author = {M. L. Byalyi and L. V. Polterovich},
     title = {Lagrangian projections of invariant tori of {Hamiltonian} systems with two degrees of freedom},
     journal = {Funkcionalʹnyj analiz i ego prilo\v{z}eni\^a},
     pages = {65},
     publisher = {mathdoc},
     volume = {23},
     number = {1},
     year = {1989},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/FAA_1989_23_1_a8/}
}