This article is also available in Nederlands
I came across it quite by accident: postcards with a small explanation in French of the publisher DESAIX. They carry a nice stamp (but there are also without). More I have not (yet) found out.
Unfortunately these cards are hard to find and my collection is far from complete. However, now that I have more than 10, it was the right time to show them in my collection:
This article is also available in Nederlands