@article{JNSA_2016_9_1_a9,
     author = {Qingyu, Zheng and Hongwei, Li},
     title = {Center and pseudo-isochronous conditions in a quasi analytic system },
     journal = {Journal of nonlinear sciences and its applications},
     pages = {102-111},
     publisher = {mathdoc},
     volume = {9},
     number = {1},
     year = {2016},
     doi = {10.22436/jnsa.009.01.10},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.22436/jnsa.009.01.10/}
}