@incollection{SB_1962-1964__8__241_0,
     author = {Douady, Adrien},
     title = {D\'emonstration \'el\'ementaire d'un th\'eor\`eme de p\'eriodicit\'e de {Bott}},
     booktitle = {S\'eminaire Bourbaki : ann\'ees 1962/63 - 1963/64, expos\'es 241-276},
     series = {S\'eminaire Bourbaki},
     note = {talk:259},
     pages = {241--249},
     publisher = {Soci\'et\'e math\'ematique de France},
     number = {8},
     year = {1964},
     mrnumber = {1611545},
     zbl = {0136.21002},
     language = {fr},
     url = {http://www.numdam.org/item/SB_1962-1964__8__241_0/}
}