Inc. BarCharts 
APA Guidelines [PDF ebook] 

Rules of punctuation, reference citation, structure and format for these commonly used guidelines. Different guidelines will be used depending on the subject area or the professor or teacher. Having a quick reference handy can speed the writing and editing process allowing the writer to focus on the quality of the paper rather than the structure. Suggested uses: o Students Handy reference while writing papers, collect the set of guides you need for your classes to easily switch between styles o Professors/Teachers Keep handy while writing for academic journals in your subject area