It is often said (e.g. , ) that, around the time of the signing of the Treaty of Versailles, Supreme Allied Commander Ferdinand Foch said "This is not peace. It is an armistice for twenty years" (but probably in French).
Foch was the Supreme Allied Commander at the time of the Armistice. Given his general stance, it is usually claimed that he said this while advocating the imposition of harder penalties.
Some sources (e.g. Wikipedia) attribute the popularisation of this Foch quote to Churchill.
Is an authentic quote of Foch, approximately contemporaneous with Versailles?
My own searches have only led to questionable or harder-to-obtain, offline sources.