Britannica Online
Encyclopedia.com
Columbia Encyclopedia
Philip's Encyclopedia
The Columbia Encyclopedia
The Crystal Reference Encyclopedia
The Hutchinson Encyclopedia, Helicon
The Macmillan Encyclopedia

The Oxford English Dictionary
American Heritage Dictionary of the English Language
AskOxford.com
Cambridge Dictionaries Online
Merriam-Webster Online
OneLook Dictionary
Chambers 21st Century Dictionary
Collins English Dictionary
Merriam-Webster's Collegiate(R) Dictionary
Visual Thesaurus
The Macquarie Dictionary
The Penguin English Dictionary

Roget's Interactive Thesaurus
Roget's II
Visual Thesaurus
Bloomsbury Thesaurus
Roget's II: The New Thesaurus

National Geographic Map
World Sites Atlas
CIA World Factbook
NationalAtlas.gov
HRW World Atlas
Maps Area

InfoPlease
The Old Farmer's Almanac
Guinness World Records

Citing Sources (from Duke University)

U.S. Census Information
Statistical Abstract of the United States
Fedstats
State and Metropolitan Area Data Book
County and City Data Book
Price's List of Lists

A Biographical Dictionary of Artists, Andromeda
The Bloomsbury Guide to Art
The Bridgeman Art Library Archive
The Cambridge Guide to Theatre
Chambers Film Factfinder
Miller's Antiques Encyclopedia
The Thames & Hudson Dictionary of 20th Century Architecture
The Thames & Hudson Dictionary of 20th Century Design and Designers
The Thames & Hudson Dictionary of Art Terms
The Thames & Hudson Dictionary of Art and Artists
The Thames & Hudson Dictionary of British Art
The Thames & Hudson Dictionary of Fashion and Fashion Designers
The Thames & Hudson Dictionary of Graphic Design and Designers
The Thames & Hudson Encyclopaedia of Impressionism

American National Biography
Chambers Biographical Dictionary
Debrett's Peerage and Baronetage
Debrett's People of Today
Dictionary of National Biography
The Hutchinson Dictionary of Scientific Biography
The Macmillan Dictionary of Women's Biography
The Penguin Biographical Dictionary of Women

Capstone Encyclopaedia of Business
Collins Dictionary of Business
Collins Dictionary of Economics
Dictionary of Accounting
Dictionary of Business, Peter Collin Publishing
Dictionary of E-Business
Dictionary of Economics, Wiley
Dictionary of Finance and Investment Terms, Barron's
Dictionary of Financial Engineering
Dictionary of Hotels, Tourism and Catering Management, Peter Collin Publishing
Dictionary of Human Resources & Personnel Management, Peter Collin Publishing
Dictionary of Library and Information Management, Peter Collin Publishing
Dictionary of Printing and Publishing, Peter Collin Publishing
The Penguin Business Dictionary
The Penguin Dictionary of Economics
The Penguin International Dictionary of Finance
The Ultimate Business Library, Wiley
Wall Street Words
Webster's New World Finance and Investment Dictionary

The American Heritage® Dictionary of the English Language
Bloomsbury Thesaurus
Chambers 21st Century Dictionary
Collins English Dictionary
The Macquarie Dictionary
Merriam-Webster's Collegiate(R) Dictionary
The Penguin English Dictionary 
Roget's II: The New Thesaurus

Benders' Dictionary of Nutrition and Food Technology
International Dictionary of Food and Cooking, Peter Collin Publishing
The New Food Lover’s Companion, Barron’s
The New Wine Lover's Companion, Barron's
Oddbins Dictionary of Wine

CIA World Factbook
The Collins World Atlas Gazetteer
The Dictionary of Human Geography
The Dictionary of Physical Geography
Holidays, Festivals, and Celebrations of the World Dictionary
The Houghton Mifflin Dictionary of Geography
The Hutchinson World Weather Guide
Merriam-Webster's Geographical Dictionary
Penguin Encyclopedia of Places
Philip's World Geo-Factbook

Andromeda Encyclopedic Dictionary of World History
Black Firsts
Chambers Dictionary of World History
The Companion to British History, Routledge
Concise Atlas of World History, Andromeda
Dictionary of British History
A Dictionary of Contemporary History - 1945 to the present
The Encyclopaedia of the Renaissance
Encyclopedia of North American Indians, Houghton Mifflin
The Great American History Fact-Finder
A Guide to the Ancient World, H.W. Wilson
The Hutchinson Chronology of World History
The Macquarie Encyclopedia of Australian Events
The New Dictionary of Cultural Literacy, Houghton Mifflin
The Reader's Companion to American History
The Reader's Companion to Military History
The Reader's Companion to U.S. Women's History
Ships of the World, Houghton Mifflin
The Reader's Companion to British History
The Thames & Hudson Dictionary of the Italian Renaissance
Who's Who in Ancient Egypt, Routledge
Who's Who in Gay and Lesbian History, Routledge
Who's Who in The Roman World, Routledge

The American Heritage® Abbreviations Dictionary
The American Heritage® Dictionary of Idioms
Bloomsbury Dictionary of Contemporary Slang
The Bloomsbury Good Word Guide
Brewer's Dictionary of Modern Phrase and Fable
Brewer's Dictionary of Phrase and Fable, Millennium Edition
The Browser's Dictionary of Foreign Words and Phrases
Chambers Dictionary of Eponyms
The Devil's Dictionary
Dictionary of Foreign Phrases and Abbreviations, H.W. Wilson
Dictionary of Languages
A Dictionary of Linguistics and Phonetics
Brewer's Dictionary of Modern Phrase and Fable
Chambers Dictionary of Eponyms
Dictionary of Foreign Phrases and Abbreviations
Divided by a Common Language
The Penguin Rhyming Dictionary
Rawson's Dictionary of Euphemisms and Other Doubletalk
Rawson's Wicked Words

Collins Dictionary of Law
Dictionary of Conflict Resolution, Wiley
Dictionary of Law, Peter Collin Publishing
Encyclopedia of the European Union
Eurojargon
Great American Court Cases, Gale
Merriam-Webster's Dictionary of Law
World of Criminal Justice, Gale

The Bloomsbury Dictionary of English Literature
Brewer's Curious Titles
The Cambridge Guide to Children's Books in English
The Cambridge Guide to Literature in English
The Cambridge Guide to Women's Writing in English
The Columbia Companion to the Twentieth-Century American Short Story
The Continuum Encyclopedia of American Literature
The Continuum Encyclopedia of British Literature
The Continuum Encyclopedia of Children's Literature A Dictionary of Literary Symbols
Dictionary of Shakespeare, Peter Collin Publishing

The American Heritage Stedman's Medical Dictionary
Baillière's Midwives' Dictionary
Black's Medical Dictionary
Churchill Livingstone's Dictionary of Nursing
Collins Dictionary of Medicine
Dictionary of Medical Acronyms & Abbreviations
Dictionary of Medicine, Peter Collin Publishing
Dictionary of Optometry and Visual Science
Dorland's Illustrated Medical Dictionary
International Dictionary of Homeopathy
Macmillan Dictionary of Toxicology
Merriam-Webster's Medical Desk Dictionary
Mosby's Dental Dictionary
Mosby's Dictionary of Complementary and Alternative Medicine
Mosby's Emergency Dictionary
Mosby's Handbook of Herbs & Natural Supplements
Mosby's Medical, Nursing and Allied Health Dictionary
Natural Medicine Instructions for Patients
Pharmaceutical Medicine Dictionary
The Royal Society of Medicine Health Encyclopedia
The Royal Society of Medicine: Medicines
Saunders Comprehensive Veterinary Dictionary
Taber's Cyclopedic Medical Dictionary
Webster's New World™ Medical Dictionary

The Faber Companion to 20th Century Popular Music
The Harvard Biographical Dictionary of Music
The Harvard Dictionary of Music
The Penguin Dictionary of Music

Bloomsbury Guide to Human Thought
The Cambridge Dictionary of Philosophy
The Concise Corsini Encyclopedia of Psychology and Behavioral Science
A Dictionary of Philosophy, Macmillan
The Penguin Dictionary of Psychology

Bloomsbury Biographical Dictionary of Quotations
Bloomsbury Thematic Dictionary of Quotations
Chambers Classic Speeches
Collins Concise Dictionary of Quotations
Rawson's Dictionary of American Quotations
Respectfully Quoted
Simpson's Contemporary Quotations

Atlas of the Bible, Andromeda
Bloomsbury Dictionary of Myth
Book of Bible Quotations
Dictionary of Hindu Lore and Legend, Thames & Hudson
Dictionary of Jewish Lore and Legend, Thames & Hudson
The Holy Bible, King James Version, Cambridge University Press
Macmillan Dictionary of the Bible
The Qur'an
Who's Who in Christianity, Routledge
Who's Who in Classical Mythology, Routledge
Who's Who in the New Testament, Routledge
Who's Who in the Old Testament, Routledge

Academic Press Dictionary of Science and Technology
Astronomy Encyclopedia
Atlas of the Universe
The Cambridge Dictionary of Scientists
Collins Dictionary of Astronomy
Collins Dictionary of Biology
Dictionary of Astronomy, Peter Collin Publishing
Dictionary of Developmental Biology and Embryology, Wiley
Guide to Gems
Guide to Global Hazards
Guide to Minerals, Rocks and Fossils
Guide to Seashells of the World
Guide to Stars and Planets
Guide to the Oceans
Illustrated Dictionary of Science, Andromeda
The Macquarie Dictionary of Trees & Shrubs
McGraw-Hill Concise Encyclopedia of Science and Technology
McGraw-Hill Dictionary of Scientific and Technical Terms
The New Penguin Dictionary of Science
The Penguin Dictionary of Mathematics
The Penguin Dictionary of Physics

The Blackwell Dictionary of Political Science
The Blackwell Dictionary of Sociology
Collins Dictionary of Sociology
A Dictionary of Diplomacy
Dictionary of Government and Politics, Peter Collin Publishing
Dictionary of Media Studies
The Encyclopedia of Ecology and Environmental Management, Blackwell Science
Macquarie Dictionary of Australian Politics
Penguin Dictionary of Sociology
U.S. Census 2000 State & County Statistical QuickFacts
World of Sociology, Gale

Collins Dictionary of Computing
Compact American Dictionary of Computer Words
Computer Graphics Companion
Dictionary of Communications Technology: Terms, Definitions and Abbreviations, Wiley
Dictionary of Engineering Terms, Butterworth-Heinemann
Dictionary of Multimedia and Internet Applications: A Guide for Developers and Users
Dictionary of Personal Computing and the Internet, Peter Collin Publishing
Encyclopedia of Computer Science
Focal Dictionary of Telecommunications, Focal Press
Hargrave's Communications Dictionary, Wiley
Harris, Dictionary of Architecture and Construction
Newnes Dictionary of Electronics, Newnes
Webster's New World™ Computer Dictionary