The Best Punctuation Book, Period., by June Casagrande, is an excellent reference that lives up to its title.
The Blue Book of Grammar and Punctuation, by Jane Straus, Lester Kaufman, and Tom Stern, is a breezy and practical guide to keep by your side.
The Chicago Guide to Grammar, Usage, and Punctuation, by Bryan A. Garner, provides one of the most thorough, comprehensive explanations of the parts of speech I have read.
The Classic Guide to Better Writing, by Rudolf Flesch and A.H. Lass, is an old treasure I always had but only recently discovered.
Dreyer’s English, by Benjamin Dreyer, is an informative guide to clarity and style written in Dreyer’s concise and humorous prose, which draws from over twenty years of his copyediting experience.
The Elements of Style, by William Struck Jr.and E.B. White, is still a good reference for clear, no-nonsense writing.
HBR Guide to Better Business Writing, by Bryan A. Garner, is brief and helpful for daily writing in your job.
Mortal Syntax, by June Casagrande, is an informative read on the clobbered usage of grammar.
Nicely Said, by Nicole Fenton and Kate Kiefer Lee, is a required reading for anyone who writes content on the web.
On Writing Well, by William Zinsser, reminds me the reason I have been blogging for over ten years.
Origins of the Specious, by Patricia T. O’Conner and Stewart Kellerman, debunks words and usage that are often misunderstood.
Woe is I, by Patricia T. O’Conner, makes grammar refreshingly clear and enjoyable.
Word by Word, by Kory Stamper, is a fun and fascinating read that will make you appreciate the art, science, and hard work invested into a lexicon.