This handout from the University of Vermont provides a detailed explanation of a literature review. It discusses how to assess a source and fill a gap in your review.
This guide from the University of Toronto provides an explanation of literature reviews and a list of questions to ask yourself about your argument and the sources you're reviewing.
This worksheet from the Purdue OWL walks the writer through organizing their literature review and making sure they demonstrate the gaps in current research.
Print and eBooks
The Literature Review
How to Read a Paper
Health Sciences Literature Review Made Easy
Doing a Literature Review in Health and Social Care