@incollection{AST_1984__113-114__96_0, author = {F\'elix, Yves}, title = {Espaces formels et $\Pi$-formels}, booktitle = {Homotopie alg\'ebrique et alg\`ebre locale}, author = {Collectif}, series = {Ast\'erisque}, publisher = {Soci\'et\'e math\'ematique de France}, number = {113-114}, year = {1984}, zbl = {0546.55013}, mrnumber = {749045}, language = {fr}, url = {http://archive.numdam.org/item/AST_1984__113-114__96_0/} }