Review articles: If you are unsure of where to start, try finding a review article. They summarize the state of research on a scientific topic at the time of publication. Many databases (including PubMed & Web of Science) allow you to limit your search to include only review articles or literature reviews. Review articles summarize what's been published in a subject area, so they are a great way to get started on a topic.
Bibliographies: Don't overlook the literature cited at the end of the review. The bibliography contains a wealth of information about the key discoveries & main researchers in the field.
Evaluating Sources: If you're looking for help on identifying good sources, check out our tutorials on evaluating sources.