@incollection{AST_1976__38-39__53_0,
     author = {Flajolet, P. and Steyaert, J. M.},
     title = {Hi\'erarchies de complexit\'e et r\'eductions entre probl\`emes},
     booktitle = {Journ\'ees algorithmiques},
     series = {Ast\'erisque},
     pages = {53--72},
     publisher = {Soci\'et\'e math\'ematique de France},
     number = {38-39},
     year = {1976},
     mrnumber = {457164},
     zbl = {0361.68067},
     language = {fr},
     url = {http://www.numdam.org/item/AST_1976__38-39__53_0/}
}