It is considered as a list of references used in a research paper, like journals, books, encyclopedias, and websites. It is the last page of a research paper where references are organized alphabetically.

We have many bibliographic styles: APA (American Psychological Association) (http://www.apastyle.org/products/asc-landing-page.aspx), MLA (Modern Language Association) (https://style.mla.org/) , and Chicago citation.