Most Useful Reference / Encyclopedia Books

Vote on the reference or encyclopedia book you think is the most useful.
The Top Ten
Oxford Dictionary
The Chicago Manual of Style: The Essential Guide for Writers, Editors, and Publishers
Roget's Thesaurus
World Book Encyclopedia
Encyclopedia of Language and Linguistics
Columbia Encyclopedia
Encyclopedia Britannica
AP Stylebook
The Associated Press Stylebook 2019: And Briefing on Media Law
Collins Spanish Dictionary
The Contenders
The World Almanac and Book of Facts
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