Earlier in the year I showed the Rondinax page from the 1939 German edition of the Agfa Catalogue. It was my impression that this was a well-thumbed full catalogue used by a retailer. A few days ago I found on the flyleaf the following sticker:

xxx1 A quick Google search soon showed that this business Otto H Kratzsch in Chemnitz is still there and that it was founded in the 19th Century, originally as a pharmacy.