Online

• Oxford Handbook of Greek & Roman Coinage. Metcalf, W. 2012.
• American Numismatic Society’s MANTIS
  The ANS collections database contains information on more than 600,000 objects in the Society’s collections. These include, coins, paper money, tokens, ‘primitive’ money, medals and decorations, from all parts of the world, and all periods in which such objects have been produced.
• Sylloge Nummorum Graecorum
  SNG publishes illustrated catalogues of Greek coins in public and private collections in the British Isles, including coins produced by all ancient civilisations of the Mediterranean and neighbouring regions except Rome, though it does include the Roman Provincial series often known as ‘Greek Imperials’.
• Ptolemaic Coins Online
  This database provides wide access to the coins listed in the print volumes of Coins of the Ptolemaic Empire by Catharine C. Lorber, the first attempt to provide a new, comprehensive standard typology and catalogue for the coinage produced by the Ptolemaic dynasty of Egypt since Ioannis Svoronos’s Τα νομίσματα τοῦ κράτους των Πτολεμαίων published in 1904–1908. 
• Coins of the Roman Republic Online (CRRO)
  Coins from the beginning of the 3rd century BC up until the Battle of Actium in 31 BC issued under the Roman Republic in Rome but not coins struck by non-Roman issuers in Italy.
• Coin hoards of the Roman Republic Online (CHRR Online)
  Database of Roman Republican coin hoards mainly from the period 155 BC to AD 2.
• Online Coins of the Roman Empire (OCRE)
  Joint project of the American Numismatic Society and the Institute for the Study of the Ancient World at New York University to create a digital corpus of the coinage of the Roman Empire.
• Portable Antiquities Scheme Introduction to Roman Coins
  A short guide to emperors, dynasties, denominations, and mints that is helpful in explaining some of the terminology that you will find in Roman coins literature and resources. It also explains how to search for Roman coins on the Portable Antiquities Scheme Database.
• Portable Antiquities Scheme Database
  This database can be used to search for Roman coins found through metal-detecting in the UK. It contains details of more than 140,000 Roman coin finds.
• Roman provincial coinage online
  This database presents an authoritative account of the coins minted in the provinces of the empire and shows how they can be regarded as an integral part of the coinage minted under the Roman emperors.
• Online Catalogue of Byzantine Coins
  Database of the 12,000 Byzantine coins held by Dumbarton Oaks.
• Online Catalogue of Byzantine Seals
  Ongoing project to record and publish the 17,000 Byzantine lead seals held by Dumbarton Oaks.

In Print

• Roman Republican Coinage. Crawford, Michael. London; New York: Cambridge University Press, 1974.
  Classmark: CJ 909 V.2.
  The most important collection of coins from the Roman Republic. It does not contain plates and images, but it provides detailed descriptions and useful analysis wherever possible. To use it, you must know the ‘RRC/Crawford’ number of the coin you are looking for. (All Roman Republican coins are cited with an RRC/Crawford number). Volume one contains the catalogue with description and analysis of the coins, and volume two contains a suite of interpretative notes and specialist guidance to the use, development, and design of Roman Republican coins.
• Ancient History from Coins. Howgego, C. J.  London; New York: Routledge, 1995.
  Classmark: CJ 335 HOW
• The Hellenistic World: Using Coins as Sources. Thonemann, P. 2015.
  Classmark: DF235.A2 THO
• From Caesar to Augustus (c. 49 BC-AD 14): using coins as sources. Rowan, C.
  Classmark: CJ 833 ROW
  Aimed at undergraduate students studying the history of the late Roman Republic.