Literature Review
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“Provide a context for the research, justify the research, ensure the research hasn't been done before (or if it is repeated, that it is marked as a "replication study"), show where the research fits into the existing body of knowledge, enable the researcher to learn from previous theory on the subject, illustrate how the subject has been studied previously, highlight flaws in previous research, outline gaps in previous research, show that the work is adding to the understanding and knowledge of the field, help refine, refocus or even change the topic.”
If you manage to develop a review which is able to address these ten points then I would say this is a perfect review.
Photo by Yazdan Mansourian: Cambridge, Trinity College, April 2006.