A few months ago I bought a Franz Heide cranberry cabochon pokal, which came with a CD catalogue of Franz Heide pieces from the 1920s & 30s - for which I was most grateful. Shows so many of those "Moser" cabochon pieces which appear on Ebay!
These catalogues are a fabulous resource for people like me who love glass but don't have the benefit of the museums and exhibitions in our countries. They are not always easy to find ...