@incollection{SB_1960-1961__6__141_0,
     author = {Shapiro, Arnold},
     title = {Alg\`ebres de {Clifford} et p\'eriodicit\'e des groupes $\pi _k(BO)$},
     booktitle = {S\'eminaire Bourbaki : ann\'ees 1960/61, expos\'es 205-222},
     series = {S\'eminaire Bourbaki},
     note = {talk:215},
     pages = {141--148},
     publisher = {Soci\'et\'e math\'ematique de France},
     number = {6},
     year = {1961},
     zbl = {0116.26102},
     language = {fr},
     url = {http://www.numdam.org/item/SB_1960-1961__6__141_0/}
}