Reference works can be a good place to begin your research, as they generally provide background information and often cite longer, more authoritative research works on the topic.
Use UC Library Search to search for encyclopedia, dictionary, and other reference entries by limiting search results to Resource Type: "Reference Entries." To find content that is available in ebooks and online resources, limit to "Available Online."
Alternately, use the Resource Type limit "Book Chapters" to find longer overviews.