APA is likely the most common citation style that you will use in Criminology classes, but when in doubt, always check with your professor. Purdue OWL has an excellent APA Guide available online, that contains information about citations, formatting, and basic style. A print copy of the official handbook is also available at the Research Help desk, in the reference collection.
Publication Manual of the American Psychological Association by Because Criminology involves interdisciplinary coursework, you may need to use a variety of citation styles; resources for the major citation styles are available below. Give credit where credit is due. By properly citing the sources you use in your research projects you are both identifying the resources that you used to complete your work and you are formally acknowledging the authors or creators of those resources.