@article{AIF_2013__63_4_1367_0,
     author = {Gaiv\~ao, Jos\'e Pedro},
     title = {Analytic invariants for the $1:-1$ resonance},
     journal = {Annales de l'Institut Fourier},
     pages = {1367--1426},
     publisher = {Association des Annales de l{\textquoteright}institut Fourier},
     volume = {63},
     number = {4},
     year = {2013},
     doi = {10.5802/aif.2806},
     zbl = {06359592},
     mrnumber = {3137358},
     language = {en},
     url = {http://www.numdam.org/articles/10.5802/aif.2806/}
}