@book{AST_1977__50_,
     author = {Collectif},
     title = {Syst\`emes dynamiques {II} - {Varsovie}},
     series = {Ast\'erisque},
     publisher = {Soci\'et\'e math\'ematique de France},
     number = {50},
     year = {1977},
     language = {mul},
     url = {http://archive.numdam.org/item/AST_1977__50_/}
}