Reference request: localisation of categories I'm trying to track down a result mentioned in Verdier's _Categories Derivees_ appearing in SGA 4.5. In chapter 2, 3.1 (page 280 in SGA 4.5) Verdier mentions that categorical localisations always exist, and cites [C.G.G] for this result. The problem is, [C.G.G] does not appear anywhere else in SGA 4.5 (in particular, it is not in the bibliography). Does anyone have any idea what paper / book Verdier is referring to here?

Here's a guess.

From the bibliography of Schiffmann Gérard's Théorie élémentaire des catégories (1962) which can be found on page 33 of Séminaire Banach (1972):

!Chevalley, Gabriel et Grotendieck - " Catégories et foncteurs " - A paraître

(It may be hard to find or lost as Chevalley had a habit of only keeping a single copy of his papers.)