@incollection{AST_1984__113-114__44_0,
     author = {Baues, Hans Joachim},
     title = { The chains on the loops and $4$-dimensional homotopy types},
     booktitle = {Homotopie alg\'ebrique et alg\`ebre locale},
     series = {Ast\'erisque},
     pages = {44--59},
     publisher = {Soci\'et\'e math\'ematique de France},
     number = {113-114},
     year = {1984},
     mrnumber = {749042},
     zbl = {0555.55007},
     language = {en},
     url = {http://archive.numdam.org/item/AST_1984__113-114__44_0/}
}