Citation Web Guides

Acton-Boxborough Regional High School Guide to Writing and Research (MLA based):

APA: (American Psychological Association) used in the sciences & social sciences
Purdue OWL: APA Guide:
APA Style:

MLA: (Modern Language Association) used in literature & other humanities
Purdue OWL: MLA Guide:

Chicago: Author-date Style: used in social sciences
Chicago Manual of Style Quick Guide (click on author-date tab):

Chicago: Notes-bibliography style: used in arts, literature, history
Purdue OWL: Chicago Manual of Style Guide:
Chicago Manual of Style Quick Guide (notes-bibliography is the default tab):

Turabian: (a simplified Chicago style) used in humanities, social & natural sciences

Research and Documentation Online 5th Edition by Diana Hacker and Barbara Fister
covers MLA, APA, Chicago and the CSE (Council of Science Editors)

Online Citation Generators

CiteThisForMe : "Automatically create your bibliographies, citations, and works cited lists in the correct format using the APA, MLA, Chicago, Vancouver, or Harvard referencing styles - instantly!"

EasyBib : "Free Automatic Bibliography and Citation Maker. Save time by creating a Works Cited page instantly in MLA, APA, or Chicago!"

Plagtracker's Citation Generator :  Citation gererator helps you cite web resources, books, and periodicals in APA, MLA, or Chicago style.