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GEN: Understanding the Many Types of Information Found in Libraries


Reference Sources

What They Are

Use Them When You Need...

Summaries of facts, definitions, histories, statistics, and other types of information on large subject areas, organized for quick lookup.

  • Basic overviews of new subjects when you're getting started.
  • Quick lookup of factual info.
  • Recommendations for more detailed sources (like books and articles).

Why use them?

Reference sources are generally the place to begin your research, especially when you're starting out with an unfamiliar field. But they're also where you return when you need to look up formulas, facts, definitions, and other standard details; they tend to pack a lot of information into simple, easy-to-use packages.

Scholarly Sources

Reference sources are rarely peer-reviewed. In fact, because they mostly contain established, factual information, they're sometimes not even cited in academic works, unless directly quoted. Check your style manual for best guidelines.

Primary or Secondary Sources

As compilations of existing information, reference works are decisively in the category of secondary sources.


Online Encyclopedias

Encyclopedia Britannica

The Encyclopedia Britannica is considered to be one of the most  authoritative encyclopedias around.  In addition to the encyclopedia articles you can find primary sources and multimedia.

CREDO Reference

Search in CREDO in hundreds of encyclopedias, dictionaries, thesauri, quotations, and subject-specific titles, as well as 200,000+ images and audio files, and nearly 200 videos.  There is also a great Mind Map to help you expand your topic or sharpen its focus.

Gale eBooks

Gale eBooks offer number of specialized encyclopedias available as the online version of print resources.

What About Wikipedia?

Because Wikipedia content is anonymous and lacks a formal review process, it's not considered a "scholarly source," and most teachers don't accept Wikipedia citations in papers. That said, Wikipedia does increasingly cite sources, so you can use it to lead you to sources which you can cite.

Encyclopedias attempt to provide comprehensive summaries of knowledge in either a specific field (subject encyclopedias) or "everything" (general encyclopedias). Encyclopedias are typically divided into a collection of articles on discrete topics. Academically oriented encyclopedias will often include short bibliographies, making them a good resource for identifying key books and articles on a topic.