Biography and names
- VIAF (Virtual International Authority File) / OCLC
- LCNAF (Library of Congress Name Authority File)
- CERL Thesaurus / Consortium of European Research Libraries
- Names of Persons : national usages for entry in catalogues (4th revised and enlarged edition, 1996) [PDF] / IFLA (International Federation of Library Associations and Institutions)
- ULAN (Union List of Artist Names Online) / The Getty Research Institute
- RKDartists& / RKD – Nederlands Instituut voor Kunstgeschiedenis
- Cultural Objects Name Authority Online / The Getty Research Institute
- Biographie universelle ancienne et moderne (2e éd., 1843) / Louis-Gabriel Michaud
- Deutsche Biographie / Historische Kommission bei der Bayerischen Akademie der Wissenschaften
- Historisches Lexikon der Schweiz
- ARLIMA (Les Archives de littérature du Moyen Âge)
- The List of Popes / New Advent
- The Cardinals of the Holy Roman Church / Salvador Miranda
- On-line Calendar of Saints Days / Glenn Gunhouse
- The Martyrology of the Sacred Order of Friars Preachers
- Internet Medieval Source Book : saints’ lives / Paul Halsall
- Nobilario de los Conquistadores de Indias (1892) [digitized copy] / la Sociedad de Bibliofilos Españoles
Calendars and computes
- Calendar Tools / O. Lieberknecht
- The Perpetual Calendar : a helpful tool to postal historians / Toke Nørby
- Calculate / CalendarHome.com
- Roman Calendar : conversion to our calendar / Paul Lewis
- Ian’s English Calendar : an online handbook of dates for English history & literature / Ian MacInnes
- The French Republican Calendar [archived site] / Philippe Chapeli
- Calculate the Date of Easter & Other Moveable Holidays / Ian MacInnes
- Zeitrechnung des Deutschen Mittelalters und der Neuzeit / H. Grotefend ; H. Ruth
- The Calendoscope / D. Muzerelle ; Institut de recherche et d’histoire des textes
Languages
General
- Grammar and Language Courses [archived site] / Yourdictionary.com
- Designators by Language / Princeton University
- AACR2 abbreviations (Roman Alphabet) / Yale University
Latin
- RBMS/BSC Latin Place Names File / Robert L. Maxwell ; RBMS Bibliographic Standards Committee
- Glossary of Common Latin Terms Found in Imprints of Early Printed Books / Robert L. Maxwell
- Glossa : a Latin dictionary / Orbilius
- Guide to Latin Prepositions / Later Latin Society
- Numen : the Latin lexicon / Keith Alexander Woodell
- Allen and Greenough’s New Latin Grammar
- Latin Dictionary Headword Search Results / Perseus Project
- Thesaurus Eruditionis / CAMENA (Corpus Automatum Multiplex Electorum Neolatinitatis Auctorum) ; TERMINI (Vernetzter Wortschatz lateinischer Wissensliteratur der Frühen Neuzeit) ; Deutschen Forschungsgemeinschaft
- The Young Secretary’s Guide [Google Books] / John Hill
Greek
- Greek Dictionary Headword Search Results / Perseus Project
- Pollux : Archimedes Project dictionary access / Archimedes Project, Harvard University
- ΛΟΓΕΙΟΝ = Logeion / University of Chicago
German
- Abbreviations and German Words Found in Graesse / RBMS Bibliographic Standards Committee
- Deutsches Wörterbuch / Jacob Grimm und Wilhelm Grimm / Wörterbuchnetz des Trier Center for Digital Humanities
Place/geographic
- GNS (Geographic Names Server) / NGA (National Geospatial-Intelligence Agency)
- BGN (U.S. Board on Geographic Names)
- Getty Thesaurus of Geographic Names Online / The Getty Research Institute
- CGNDB (Canadian Geographical Names Data Base)
- Topographical Dictionaries : a series of topographical dictionaries for England, Scotland and Wales, compiled by the publisher Samuel Lewis / British History Online
- RBMS/BSC Latin Place Names File / Robert L. Maxwell ; RBMS Bibliographic Standards Committee
- Orbis Latinus : Lexikon lateinischer geographischer Namen des Mittelalters und der Neuzeit. Band 1 A-D (1972) [digitized copy] / J. G. Th. Graesse ; Friedrich Benedict ; Helmut Plechl