@article{RCM_1992__26_1-4_181852,
     author = {J. Billeke and H., Wallace, M. Burgos},
     title = {Melnikov deviations and limit cycles for {Lienard} equations},
     journal = {Revista colombiana de matematicas},
     pages = {3--26},
     publisher = {mathdoc},
     volume = {26},
     number = {1-4},
     year = {1992},
     zbl = {0774.34021},
     url = {http://geodesic.mathdoc.fr/item/RCM_1992__26_1-4_181852/}
}