A literature review surveys books, scholarly articles, and any other sources relevant to a particular issue, area of research, or theory, and by so doing, provides a description, summary, and critical evaluation of these works in relation to the research problem being investigated. Literature reviews are designed to provide an overview of sources you have explored while researching a particular topic and to demonstrate to your readers how your research fits within a larger field of study.-- Fink, Arlene. Conducting Research Literature Reviews: From the Internet to Paper, 2014.

Questions to ask yourself:
How completely do you understand the topic?
Are you familiar with the past and current literature on the topic?
Who is/are the authority(s) in the field of study?
Has each source been evaluated critically?
Which sources are factually questionable?