@article{urn:eudml:doc:39684,
title = {Monotonicity of the period map of a non-Hamiltonian center.},
journal = {Collectanea Mathematica},
volume = {45},
year = {1994},
pages = {177-182},
zbl = {0812.34018},
mrnumber = {MR1316935},
language = {en},
url = {http://dml.mathdoc.fr/item/urn:eudml:doc:39684}
}
Billeke, Jorge; Sáez, Eduardo. Monotonicity of the period map of a non-Hamiltonian center.. Collectanea Mathematica, Tome 45 (1994) pp. 177-182. http://gdmltest.u-ga.fr/item/urn:eudml:doc:39684/