Various disciplines prefer to use styles other than MLA and APA. This page has resources for some of the more common ones.
Ask your instructors which style they expect you to use and feel free to consult with a librarian about citing your sources.
Use the American Chemical Society style for your chemistry papers.
Use Chicago/Turabian for your history, humanities, and arts papers.
Use CSE for you natural sciences courses, such as biology, mathematics, and physics.