Columbia subject headings:
Gems, Ancient--Catalogs.
Gems, Classical--Germany--Bonn--Catalogs.
Gems--Germany--Bonn--Catalogs.
Rheinisches Landesmuseum Bonn--Catalogs.
Harvard subject headings:
Gems, Ancient--Catalogs.
Gems, Classical--Catalogs.
Gems, Roman--Catalogs.
Gems--Germany--Bonn--Catalogs.
Rheinisches Landesmuseum Bonn--Catalogs.
Princeton subject headings: