@incollection{AST_1985__130__237_0,
     author = {Malgrange, Bernard},
     title = {Variations g\'en\'eralis\'ees},
     booktitle = {Syst\`emes diff\'erentiels et singularit\'es},
     author = {Collectif},
     series = {Ast\'erisque},
     publisher = {Soci\'et\'e math\'ematique de France},
     number = {130},
     year = {1985},
     zbl = {0572.14012},
     mrnumber = {804056},
     language = {fr},
     url = {http://archive.numdam.org/item/AST_1985__130__237_0/}
}

Malgrange, Bernard. Variations généralisées, dans Systèmes différentiels et singularités, Astérisque, no. 130 (1985), 3 p. http://archive.numdam.org/item/AST_1985__130__237_0/