@article{02210839,
title = {Localization of periodic orbits of autonomous systems based on high-order extremum conditions.},
journal = {Mathematical Problems in Engineering},
volume = {2004},
year = {2004},
pages = {277-290},
doi = {10.1155/S1024123X04311038},
zbl = {1099.34043},
language = {en},
url = {http://dml.mathdoc.fr/item/02210839}
}
Starkov, Konstantin E. Localization of periodic orbits of autonomous systems based on high-order extremum conditions.. Mathematical Problems in Engineering, Tome 2004 (2004) pp. 277-290. doi : 10.1155/S1024123X04311038. http://gdmltest.u-ga.fr/item/02210839/