@article{120188,
author = {J\'an Andres},
title = {Symmetry in a certain simply perturbed Hamiltonian system},
journal = {Acta Universitatis Palackianae Olomucensis. Facultas Rerum Naturalium. Mathematica},
volume = {26},
year = {1987},
pages = {131-138},
zbl = {0699.34046},
mrnumber = {1033334},
language = {en},
url = {http://dml.mathdoc.fr/item/120188}
}
Andres, Ján. Symmetry in a certain simply perturbed Hamiltonian system. Acta Universitatis Palackianae Olomucensis. Facultas Rerum Naturalium. Mathematica, Tome 26 (1987) pp. 131-138. http://gdmltest.u-ga.fr/item/120188/
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