“Cite.” English Oxford Living Dictionaries, Oxford University, 2018, en.oxforddictionaries.com/definition/cite.
Each school subject may have a different 'style' of citing that you need to use to justify your argument. Also, you need to cite to show your instructors where you got your evidence.
*Your research includes any speeches, presentations, or papers that you produce using outside sources.
When in doubt, cite!