DUFF (E. Gordon). Fifteenth Century English Books. A Bibliography of Books and Documents Printed in England and of Books for the English Market Printed Abroad.1917

Oxford: The Bibliographical Society, First edition, [x], 136pp., 4to, 53 facsimiles, orig. cloth-backed boards, t.e.g. A complete listing, as known at the time, of all extant copies of 15th-century English books. Has 431 entries with detailed descriptions of the different imprints, noting variations where pertinent. Also provides location of copies.