{{short description|Index or textual consolidation of primary and secondary sources}} {{Distinguish|Tertiary sector of the economy}} {{For|Wikipedia's policy on the use of tertiary sources|Wikipedia:No original research#Tertiary}} A '''tertiary source''' is an index or textual consolidation of already published primary and secondary sources<ref name="umd">[https://guides.lib.odu.edu/informationliteracytutorials Primary, secondary and tertiary sources.] {{Webarchive|url=https://web.archive.org/web/20130703015116/http://www.lib.umd.edu/ues/guides/primary-sources |date=2013-07-03 }}". University Libraries, University of Maryland. Retrieve 07/26/2013</ref> that does not provide additional interpretations or analysis of the sources.<ref>{{cite web|url=http://www.lib.odu.edu/genedinfolit/1infobasics/tertiary_information_sources.html|title=Tertiary Information Sources|date=September 2012|publisher=Old Dominion University -- ODU Libraries|access-date=20 June 2013|archive-date=6 September 2019|archive-url=https://web.archive.org/web/20190906194053/http://www.lib.odu.edu/genedinfolit/1infobasics/tertiary_information_sources.html|url-status=dead}}</ref><ref name=JCU>"[http://libguides.jcu.edu.au/tertiary Tertiary sources] {{Webarchive|url=https://web.archive.org/web/20141106174742/http://libguides.jcu.edu.au/tertiary |date=2014-11-06 }}". James Cook University.</ref> Some tertiary sources can be used as an aid to find key (seminal) sources, key terms, general common knowledge<ref name="newhaven">"[http://libguides.newhaven.edu/content.php?pid=465151&sid=3809011 Primary, Secondary, and Tertiary Resources]". University of New Haven.</ref> and established mainstream science on a topic. The exact definition of ''tertiary'' varies by academic field.
Academic research standards generally do not accept tertiary sources such as encyclopedias as citations,<ref name="newhaven" /> although survey articles are frequently cited rather than the original publication.
== Overlap with secondary sources == As is also the case with distinguishing primary and secondary sources in some disciplines,<ref>{{cite book |last1=Kragh |first1=Helge |title=An Introduction to the Historiography of Science |date=1989 |publisher=Cambridge University Press |isbn=0-521-38921-6 |pages=121 |url=https://books.google.com/books?id=OX7d7u_2rF4C&pg=PA121 |access-date=28 November 2025}}</ref> there is not always a clear distinguishing line between secondary and tertiary sources. Depending on the topic of research, a scholar may use a bibliography, dictionary, or encyclopedia as either a tertiary or a secondary source.<ref name="umd"/> This causes some difficulty in defining many sources as either one type or the other.
In some academic disciplines, the differentiation between a secondary and tertiary source is relative.<ref name="umd"/><ref name=JCU />
In the United Nations International Scientific Information System (UNISIST) model, a secondary source is a bibliography, whereas a tertiary source is a synthesis of primary sources.<ref>{{Cite journal | last1 = Søndergaard | first1 = T. F. | last2 = Andersen | first2 = J. | last3 = Hjørland | first3 = B. | doi = 10.1108/00220410310472509 | title = Documents and the communication of scientific and scholarly information: Revising and updating the UNISIST model | journal = Journal of Documentation | volume = 59 | issue = 3 | pages = 278 | year = 2003 | s2cid = 14697793 }}</ref>
==Types of tertiary sources== {{More citations needed section|date=May 2021}} Tertiary sources can come in book form or as an online resource. Tertiary sources in book form are frequently organised in alphabetical order, whereas an online tertiary source may be searchable by keyword.<ref name=":0" />
Examples of tertiary sources include; reference books, encyclopedias, dictionaries, some textbooks,<ref name="umd" /><ref name=":0">{{Cite book |last=Bombaro |first=Christine |title=Finding History: Research Methods and Resources for Students and Scholars |date=2012 |publisher=Scarecrow Press, Incorporated |isbn=978-0-8108-8379-6 |edition=1st |location=Lanham, MD |pages=57}}</ref> abstracts, directories, factbooks, handbooks, manuals<ref>{{cite book |last1=Harris, Bitonti, Fleisher, Binderkrantz |title=The Palgrave Encyclopedia of Interest Groups, Lobbying and Public Affairs |date=2022 |publisher=Springer |isbn=9783030445553 |page=1345 Switzerland |edition=1 |url=https://books.google.com/books?id=32J2EAAAQBAJ&dq=tertiary+sources+definition&pg=PA1345 |access-date=28 November 2025}}</ref> and compendia. Indexes, bibliographies, concordances, and databases are aggregates of primary and secondary sources and therefore often considered tertiary sources. They may also serve as a point of access to the full or partial text of primary and secondary sources. Almanacs, travel guides, field guides, and timelines are also examples of tertiary sources.
Tertiary sources attempt to summarize, collect, and consolidate the source materials into an overview without adding analysis and synthesis of new conclusions.
Wikipedia is a tertiary source.<ref>{{cite web |title=Primary, Secondary, and Tertiary Sources |url=https://crk.umn.edu/library/primary-secondary-and-tertiary-sources |access-date=19 April 2023 |publisher=University of Minnesota Crookston}}</ref>{{irrelevant citation|date=April 2026|reason=The source does not state the information attributed to it.}}
==See also== * Source text * Third-party source
== References == {{Reflist}}
{{Historiography}} {{Libraries and library science}}
Category:Sources Category:History resources Category:Information science