@article{1181069780,
author = {Sabatini, M.},
title = {Li\'enard Limit Cycles Enclosing Period Annuli, or Enclosed by Period Annuli},
journal = {Rocky Mountain J. Math.},
volume = {35},
number = {6},
year = {2005},
pages = { 253-266},
language = {en},
url = {http://dml.mathdoc.fr/item/1181069780}
}
Sabatini, M. Liénard Limit Cycles Enclosing Period Annuli, or Enclosed by Period Annuli. Rocky Mountain J. Math., Tome 35 (2005) no. 6, pp. 253-266. http://gdmltest.u-ga.fr/item/1181069780/