The Manual of Style by University of Chicago & The Elements of Style by William Strunk jr.
The Manual of Style by University of Chicago Press Staff (Editor) - 9th Edition Countless publishing professionals have learned the details of their business from this classic guide for publishers, editors and writers. In the 1890s, a proofreader at the University of Chicago Press prepared a single sheet of typographic fundamentals intended as a guide for the University community. That sheet grew into a pamphlet, and the pamphlet grew into a book. Clear, concise, and replete with commonsense advice, The Chicago Manual of Style, offers the wisdom of a hundred years of editorial practice while including a wealth of new topics and updated perspectives. For anyone who works with words, whether on a page or computer screen, this continues to be the one reference book you simply must have.
The Elements of Style by William Strunk jr.
Asserting that one must first know the rules to break them, this classic reference book is a must-have for any student and conscientious writer. Intended for use in which the practice of composition is combined with the study of literature, it gives in brief space the prinicipal requirements of plain English style and concentrates attention on the rules of usage and principles of composition most commonly violated.