@article{AIHPA_1970__13_3_215_0,
     author = {Gille, J. F.},
     title = {An exponentiation theorem for unbounded derivations},
     journal = {Annales de l'I.H.P. Physique th\'eorique},
     pages = {215--220},
     publisher = {Gauthier-Villars},
     volume = {13},
     number = {3},
     year = {1970},
     mrnumber = {279595},
     zbl = {0204.44401},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/AIHPA_1970__13_3_215_0/}
}