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Library DIY

Types of sources I need

The first thing you should do when you have a research assignment is to figure out what types of article sources are required or allowed by your instructor. Some instructors require you to use only scholarly peer-reviewed journals, primary sources, newspapers, or books from the library while others might be more flexible in the types of sources used. Here are some source terms you should be familiar with:

  • Scholarly article: written by an expert in the field and reviewed by peers who are experts in the same area. In many databases, you can limit your search to scholarly, peer reviewed or refereed journals to weed out any non-scholarly content. You can learn how to identify and find them in our Finding Peer reviewed Articles.
  • Professional/trade article: trade or professional journals can have articles written by experts in the field or by staff writers. The articles are only reviewed by editors for style, so they go through a less rigorous review process. The articles often do not contain reference lists. Examples include School Library Journal, Harvard Business Review, Engineering and Mining Journal, and American Biology Teacher.
  • Popular journals: written for a general audience rather than for professionals or scholars. Examples include The New Yorker, People, and Rolling Stone.
  • Primary source: an item that was created during the period being studied and documents in some way what is being studied. Examples include newspaper accounts, government documents, letters, diaries, autobiographies, speeches, oral histories, museum artifacts, photographs.
  • Secondary source: a source that is one step removed from an event and analyzes primary sources. Examples include a book about World War II that is based on records from the time, or a journal article about Chinese immigrants to Portland. Most books and articles are secondary sources.


Next, think about what types of evidence you need to answer your research question or make your case. This chart makes suggestions for specific types of resources for your research:

If you need: Try using:
Expert evidence Scholarly articles, books, and statistical data
Public or individual opinion on an issue Newspapers, magazines, and websites
Basic facts about an event Newspapers, books, encyclopedias (for older and well-known events)
Eye-witness accounts Newspapers, primary source books, web-based collection of primary sources
A general overview of a topic Books or encyclopedias
Information about a very recent topic Websites, newspapers, and magazines
Local information Newspapers, websites, and books
Information from professionals working in the field Professional/trade journals