@article{10_4064_am32_4_4,
     author = {A. Raouf Chouikha},
     title = {Monotonicity of the period function for some planar
differential {systems.
Part} {II:} {Li\'enard} and related systems},
     journal = {Applicationes Mathematicae},
     pages = {405--424},
     publisher = {mathdoc},
     volume = {32},
     number = {4},
     year = {2005},
     doi = {10.4064/am32-4-4},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/am32-4-4/}
}