A literature review (also called a research review or review of the literature) is a summary of existing research on a topic. It reviews the scholarly "literature" on that topic. It is often a preliminary part of a publication where the author identifies and comments on the relevant previous research, but it can also be a stand-alone work.
Ferris, Dan, Ron Hayduk, Richards Alyscia, Emma Strauss Schubert, and Mary Acri. 2020. Noncitizen voting rights in the global era: A literature review and analysis. Journal of International Migration and Integration 21, (3) (09): 949-971, https://castleton.idm.oclc.org/login?url=https://www.proquest.com/scholarly-journals/noncitizen-voting-rights-global-era-literature/docview/2239964509/se-2?accountid=9930 (accessed February 3, 2022).
David, E. J. R., Tiera M. Schroeder, and Jessicaanne Fernandez. 2019. “Internalized Racism: A Systematic Review of the Psychological Literature on Racism’s Most Insidious Consequence.” Journal of Social Issues 75 (4): 1057–86. doi:10.1111/josi.12350.