Use "medieval" or "middle ages," a geographical term like "england," and a topic word such as "textiles" or "heraldry"
Bibliographies
Online Medieval Sources BibliographyProvides a searchable bibliography of texts—from private letters, wills, and household accounts to literary works, philosophical treatises, chronicles, court proceedings, church records, and a host of other documents—that were written in the Middle Ages and are now available in printed or online editions and translations.
International Medieval BibliographyComprises over 300,000 articles derived from regular coverage of some 4500 periodicals and 5000 miscellany volume (conference proceedings, essay collections, Festschriften and exhibition catalogues). All articles are classified with full bibliographical details and subject classifications and indexing familiar to medievalists.
Bibliographie de Civilisation Medievale Online: InternationalEstablished by the Centre d´Études Supérieures de Civilisation Médiévale (Université de Poitiers).Provides a current bibliography of monographs worldwide and listings of miscellany volumes (conference proceedings, essay collections or Festschriften). Currently comprises 40,000 titles from 1958 to 2003.
Early books
Early English Books Online (EEBO)Contains digital facsimile page images of virtually every work printed in England, Ireland, Scotland, Wales and British North America and works in English printed elsewhere from 1473-1700 - from the first book printed in English by William Caxton, through the age of Spenser and Shakespeare and the tumult of the English Civil War.
English Short Title Catalogue (ESTC)International union catalogue listing early books, serials, newspapers and selected ephemera printed before 1801. It contains catalogue entries for items issued in Britain, Ireland, overseas territories under British colonial rule, and the United States. Also included is material printed elsewhere which contains significant text in English, Welsh, Irish or Gaelic,
Incunabula Short Title Catalogue (ISTC)The database records nearly every item printed from movable type before 1501, but not material printed entirely from woodblocks or engraved plates. 30,375 editions are listed as of March 2014, including some 16th-century items previously assigned incorrectly to the 15th century.