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In different disciplines, the term "primary source" means different things. This page explains what historical and scientific primary sources are and how you can find them.

Historical Primary Sources

What is a historical primary source?

For historians (as well as scholars in some humanities disciplines), primary sources are sources that were either created during the time period being studied or were created at a later date by a participant in the events being studied (as in the case of memoirs). They reflect the individual viewpoint of a participant or observer.  Primary sources enable the researcher to get as close as possible to what actually happened during an historical event or time period.

Primary sources can include a variety of materials, including biographies and memories; videos and documentaries that capture news footage or an event; or newspapers and magazine articles published during the time period.


How do I find historical primary sources?

Try our list of primary source databases or consult our Subject Guides for more suggestions. For more tips on searching for historical primary sources, check out this guide to finding historical primary sources from UC Berkeley.

Primary Sources in the Sciences

What's a primary source in the sciences?

Primary sources in the sciences (and many social sciences), report original research, ideas, or scientific discoveries for the first time. Primary sources in the sciences may also be referred to as primary research, primary articles, or research studies. Examples include research studies, scientific experiments, papers and proceedings from scientific conferences or meetings, dissertations and theses, and technical reports.

The following are some characteristics of scientific primary sources:

  • They report results/findings/data from experiments or research studies.
  • They do not include meta-analyses, systematic reviews, or literature reviews.  These are secondary sources.
  • They are frequently found in peer-reviewed or scholarly journals, see What is a Scholarly Journal?.
  • They should explain the research methodology used and frequently include methods, results, and discussion sections.
  • They are factual, not interpretive.

NOTE: Finding primary sources in the history of science or medicine is the same as finding historical primary sources.  The course guide for History of Medicine is a great place to start your research.


How do I find primary sources in the sciences?

A good place to start your search is in a subject-specific database. Many of these databases include options to narrow your search by source type. Not sure which database to use? Check out our Database A-Z List (use the dropdown menu to filter by subject) or consult our Subject Guides for more in-depth help.