Metcalf, D. M., Coinage of the Crusades and the Latin East in the Ashmolean Museum, Oxford. Royal Numismatic Society Special Publication No. 15, London, 1983, 248 pages including 36 plates, hardcover with dust jacket. The only comprehensive monograph of the Crusades and the Latin East since Schlumberger. It includes descriptions of the coins of Lucca, Valence, and elsewhere that circulated in the Latin East. There is a good historical overview with maps, a checklist of hoards, ex James Farr Numismatic Library.
Estimate: 50-75 USD