Standard reference works by Arnoldsche Art Publishers, such as the Ceramic Marks Encyclopaedia 1885–1935 and Glass Marks Encyclopaedia 1600–1945, are an indispensable feature in respective museum and collectors’ libraries. Publications on individual topics of collecting such as furniture (Louis Philippe Möbel), ceramics (Bunzlauer Keramik) and metal (Historic Cutlery) as well as monographs on renowned companies (Kayserzinn) offer well-founded background information, aiding the assignation and classification of collector’s items. Overviews (Die Jugend der Moderne) and reprints (Dokumente zum Jugendstil, Ideen von Olbrich) can also be found in the collectors’ section.