@article{DAN_1970_192_4_a14,
     author = {G. M. Zaslavsky},
     title = {On the change of the adiabatic invariant of an non-linear periodic wave},
     journal = {Doklady Akademii Nauk},
     pages = {760--763},
     publisher = {mathdoc},
     volume = {192},
     number = {4},
     year = {1970},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1970_192_4_a14/}
}