@incollection{AST_1986__142-143__3_0,
     author = {Enguehard, Michel},
     title = {Obstructions et $p$-groupes de classe 3},
     booktitle = {R\'evision dans les groupes finis groupes du type de Lie de rang 1},
     series = {Ast\'erisque},
     pages = {3--48},
     publisher = {Soci\'et\'e math\'ematique de France},
     number = {142-143},
     year = {1986},
     mrnumber = {873957},
     language = {fr},
     url = {http://www.numdam.org/item/AST_1986__142-143__3_0/}
}