American Numismatic Association
Ancient Coin Collector's Guild
British Museum (Department of Coins and Medals)
Coinage of the Roman Republic Online (The British Museum)
Corpus of Early Medieval Coin Finds (Fitzwilliam Museum, Cambridge)
The Hermitage Museum (Numismatics)
Industry Council for Tangible Assets
Kunsthistorichesmuseum, Vienna (Numismatics)
Numismatic Guarantee Corporation
Princeton University Numismatic Collection
Professional Coin Grading Service
