The BnF in Paris used to stamp its manuscrits and printed volumes, and the stamps changed all along the history of the library. A particular stamp was in use at a particular time span, so we might be able to identify the time of the entry of a document by its stamp (this is not a precise dating, since the document might have received its stamp some years later its entry). We have an article by Josserand and Bruno about stamps on printed documents, as books, review, etc.; nobody looked at the stamps on manuscripts, which are slightly different from those used on printed material. Here is the first attempt to find a sort of comparison between the two series. I hope it would be helpful for some of you.