@article{RM_1983_38_5_a14,
     author = {L. M. Lerman and Ya. L. Umanskii},
     title = {Necessary conditions for the existence of heteroclinic trajectories in an integral {Hamiltonian} system with two degrees of freedom},
     journal = {Trudy Matematicheskogo Instituta imeni V.A. Steklova},
     pages = {150--151},
     publisher = {mathdoc},
     volume = {38},
     number = {5},
     year = {1983},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/RM_1983_38_5_a14/}
}