Ask each of your professors which style they want you to use - the information may be in your syllabus.
If they have no preference, the most common citation styles are:
| Discipline | Typical citation style(s) |
|---|---|
| Economics | APA, Chicago |
| Engineering & IT | Institute of Electrical and Electronics Engineers (IEEE) |
| Humanities | Chicago notes and bibliography; MLA |
| Law | Bluebook, Oxford Standard for the Citation of Legal Authorities (OSCOLA) |
| Medicine* | AMA, NLM, Vancouver |
| Political Science | Chicago, American Political Science Association (APSA) |
| Psychology | APA |
| Sciences | ACS, Chicago author-date, CSE |
| Social Sciences | APA, ASA, Chicago author-date |
*The field of medicine also has guidelines for ethical considerations when writing and publishing. You can read about them here: Recommendations for the Conduct, Reporting, Editing, and Publication of Scholarly Work in Medical Journals, from the International Committee of Medical Journal Editors (ICMJE).