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Primary, Secondary, and Tertiary Sources

Primary, Secondary, and Tertiary sources info-graphic. Primary sources are the raw data that include first hand-observations or contemporary accounts of events. Examples of primary sources are interviews, speeches, diaries, birth certificates, and science journal articles; secondary sources are sources that have analyzed or interpreted primary sources. These sources offer review or critique, but do not offer new evidence. They are written after the event has occurred. Examples include biographies, textbooks, journal articles, and editorials. Tertiary sources compile data on a particular topic. They are collections of primary and secondary sources, finding tools, or reference works. Examples of tertiary sources are encyclopedias, abstracts, indexes, literature reviews, library catalogs, and databases