The following reference works, many of which were used to develop this guide, are useful for more depth and detail on various subjects.
The Chicago Manual of Style, 16th edition
Associated Press Stylebook, 2016 edition
Merriam-Webster’s Collegiate Dictionary - online version of dictionary
Quick and Dirty Tips - grammar, punctuation, usage, and developments in the English language
The Little, Brown Handbook - an all-purpose complete reference