There are many books on the subject of prints, printmaking and identifying prints. Here are a few that I can personally recommend.
How To Identify Prints by Bamber Gascoigne
This comprehensive reference work provides all the answers to all the technical questions that constantly arise when trying to identify accurately any kind of print.
How Prints Look: Photographs With A Commentary
by William Ivins
An excellent introduction to prints. Through a series of enlarged details of prints in various media, Ivins makes clear the stylistic qualities peculiar to each technique. This is one of the most useful references available for learning the differences between various printmaking techniques.
Care and Identification of 19Th-Century Photographic Prints
by James M. Reilly
The book presents technical information in plain, understandable language and is supported throughout by high-quality color reproductions showing the various print types and their forms of deterioration. The pull-out flowchart gives step-by-step guidance for identifying major print types.
The Print in the Western World: An Introductory History
by Linda C. Hults
A history of the print from its origins in the fifteenth through the late twentieth century.
Medieval Craftsmen: Scribes and Illuminators
by Christopher de Hamel
Illuminated manuscripts survive in great numbers from the Middle Ages. They are often beautifully preserved, enabling us to appreciate the skilled design and craftsmanship of the people who created them.