Sources that compile and summarize information on many different, conceptually-related topics, sources such as encyclopedias, almanacs, subject dictionaries, etc., are TERTIARY sources.
TERTIARY sources usually compile information on related topics in a single work, providing information at a glance, but usually not in any great depth. Tertiary sources typically draw from secondary, and sometimes from primary, sources.
EXAMPLE:
A tertiary source summarizes information about a lot of different persons or subjects, like this dictionary of scientists.
Use Google Scholar to find academic-quality information (articles, papers, reports) on the Web.