How do scholars and researchers find primary sources? There are many discovery tools, search strategies, and practical considerations that are especially useful when conducting research with primary sources.
Primary, secondary, and tertiary sources
While primary sources are often the core of a research paper or project, researchers also depend on other types of sources to provide context, perspective, and support to analysis of primary sources.
Secondary sources analyze, interpret, and evaluate primary sources. Secondary sources typically reference or summarize primary sources and other secondary sources. Examples of secondary sources include scholarly works, textbooks, journal articles, histories, and biographies.
Tertiary or reference sources summarize and synthesize information about a topic from other sources. Tertiary sources can be a useful tool for locating primary and secondary sources. Examples of tertiary sources include encyclopedias and dictionaries, chronologies, almanacs, directories, indexes, and bibliographies.
Examples of primary, secondary, and tertiary sources by subject discipline
Painting, photograph, film
Critical review of an artist’s work
Encyclopedia article on the artist
Diary, correspondence, photograph, census data
Book about the American industrial revolution and its effect on rural culture
Timeline of the American industrial revolution
Novel, poem, manuscript, correspondence
Essay analyzing an author’s writing process
Handbook of twentieth-century authors
Treaty, government document or memo
Diplomatic history textbook
Chronology of treaties
Article presenting original scientific research, unpublished data, correspondence and original notes
Review of recent research in the field summarizing new articles, patents, etc.
Handbook of basic tables for chemical analysis
Deciding whether a source is primary or secondary is sometimes confusing. In fact, many sources can be either primary or secondary depending on the context of the research and of the source itself. For example, a medical journal article from the early 20th century looks like a secondary source but could also be used as a primary source when writing about the history of medicine. In this context, a medical journal article can be used as evidence of contemporary views of medicine during this time period. For more information on types of primary sources, explore Identify Types & Formats.