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Random House Handbook, Frederick Crews
A comprehensive handbook used by many universities.

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The Associated Press Stylebook and Libel Manual, Norm Goldstein, ed.
The stylebook for journalists. Filled with excellent references.

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The Chicago Manual of Style, University of Chicago Press
Primarily for authors, editors and copywriters. Answers esoteric questions about writing. Nice to have, but not a necessity.
The Chicago Manual of Style FAQ

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Grammar Smart: A Guide to Perfect Usage, The Princeton Review
Clear explanations and exercises in grammar and punctuation. Answers included.

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The Elements of Style, William Strunk Jr., E.B. White
An absolute must! Fewer than 100 pages. Read it once a year.

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Woe is I, Patricia T. O'Conner
Lighthearted, funny and terse, but sometimes a bit radical for purists.

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The New Well-Tempered Sentence, Karen Elizabeth Gordon
A grammar and punctuation handbook with a refreshing, whimsical approach.

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Write Right!, Jan Venolia
A small book. Easy to use.

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A Manual for Writers of Term Papers, Theses, and Dissertations, Kate L. Turabian
Every college student should own a copy of this book.

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On Writing Well, William Zinsser
An informal guide to writing non-fiction.

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Writing to Learn, William Zinsser
How to write and think clearly about any subject.

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The Miracle of Language, Richard Lederer
Insightful, entertaining essays about writing.

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Writing the Natural Way, Gabriele Rico
Using right-brain techniques to release your expressive powers.

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The Way We Talk Now, Geoffrey Nunberg
Witty commentaries about how language shapes our view of the world.

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The Story of English, Robert McCrum, William Cran, Robert MacNeil
A stimulating and comprehensive history of spoken and written English.

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Language in Thought and Action, S.I. Hayakawa
The role of language in human life, the functions of language, and how language shapes our thinking.

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Barron's ESL Guide to American Business English, Andrea B. Geffner
Sample documents and instructions for writing, plus an overview of American business customs and culture.

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NTC's American Idioms Dictionary, Richard A. Spears
Practical reference for the everyday expressions of contemporary American English.

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How to Read a Book, Mortimer J. Adler and Charles Van Doren
The classic guide to intelligent reading.

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Webster's New World Dictionary

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We prefer Roget's hardback desk version.