@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},
     series = {Ast\'erisque},
     pages = {96--108},
     publisher = {Soci\'et\'e math\'ematique de France},
     number = {113-114},
     year = {1984},
     mrnumber = {749045},
     zbl = {0546.55013},
     language = {fr},
     url = {http://archive.numdam.org/item/AST_1984__113-114__96_0/}
}