Jaume Giné. On the Centers of Planar Analytic Differential Systems. I. J. Bifurcation and Chaos, 17(9):3061-3070, 2007. [doi]
@article{Gine07:0,
title = {On the Centers of Planar Analytic Differential Systems},
author = {Jaume Giné},
year = {2007},
doi = {10.1142/S0218127407018865},
url = {http://dx.doi.org/10.1142/S0218127407018865},
researchr = {https://researchr.org/publication/Gine07%3A0},
cites = {0},
citedby = {0},
journal = {I. J. Bifurcation and Chaos},
volume = {17},
number = {9},
pages = {3061-3070},
}