Tertiary sources compile, summarize, index, or help identify scholarly sources on a topic. They are useful for background research or to get an overview of a topic before delving into secondary or primary sources. Common tertiary sources for Industrial and Systems Engineering include handbooks and similar resources.
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Handbooks - If you're not familiar with the topic, consider checking a handbook before doing research for a project or term paper. Topics covered are typically summaries. You'll get ideas for key words, phrases, and concepts that you can use in your searches.