Watermarks uniquely identify where and when paper was made. Dated paper with a watermark is used to date other pieces sharing the mark.  The guides below collect watermarks from dated specimens and are used to detect a potential time and place for paper of unknown origin.

Print guides

Briquet, C.-M. (Charles-Moïse), 1839-1918.
Les filigranes. Dictionnaire historique des marques du papier des leur apparition vers 1282 jusqu'en 1600, avec figures dans le texte et 16, 112 facsimilés de filigranes.
Art Library Z 237.B845 1923 vol. 1-4; Also available online
The most important of the printed guides, "Briquet spent many years in archives across France, tracing watermarks from paper dated up to 1600." citation

Heawood, Edward, 1863-1949.
Watermarks, mainly of the 17th and 18th centuries.
Art Library Z 237 .H43

Churchill, W. A. (William Algernon), 1865-1947.
Watermarks in paper in Holland, England, France, etc. in the XVII and XVIII centuries and their interconnection.
Main Special Collections 676 C475W
Art Library Z 237 .C56 1967

Online guides

Watermark Databases
LIMA: Literary Manuscript Analysis, Centre for the Study of the Renaissance, University of Warwick, Coventry, England
Several watermark databases are gathered here, as well as insights about finding watermarks in print and online sources.

The Thomas L. Gravell Watermark Archive
Incorporating The University of Delaware Library's Thomas L. Gravell Watermark Collection and the unpublished Watermarks and Records from the C-M Briquet Archive (MS Briquet xxx) at the Bibliothèque de Genève
Virginia Tech, Blacksburg, Virginia

Specimens of paper with different water marks, 1377-1840
Rare Books and Special Collections, Firestone Library, Princeton University Library
371 specimens of watermarked paper, together with brief descriptions of each in a mid-nineteenth century ms. hand. Each sheet of paper has three images, recto, verso, and against a lightsheet. The recto has notes at the top describing the possible date and watermark image. The sheets are arranged chronologically.                                                            [4June2014 BQP]