@article{CTGDC_1978__19_3_223_0,
     author = {Haahti, Heikki},
     title = {Compact and small rank perturbations of conformally symplectic structures},
     journal = {Cahiers de topologie et g\'eom\'etrie diff\'erentielle},
     pages = {223--268},
     publisher = {Dunod \'editeur, publi\'e avec le concours du CNRS},
     volume = {19},
     number = {3},
     year = {1978},
     mrnumber = {546072},
     zbl = {0405.53023},
     language = {en},
     url = {http://archive.numdam.org/item/CTGDC_1978__19_3_223_0/}
}