Some examples of tertiary sources are almanacs, guide books, survey articles, timelines, and user guides. Depending on the topic of research, a scholar may use a bibliography, dictionary, or encyclopedia as either a tertiary or a secondary source.
As tertiary sources, encyclopedias and textbooks attempt to summarize and consolidate the source materials into an overview, but may also present subjective commentary and analysis (which are characteristics of secondary choices).
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.
- "Primary, secondary and tertiary sources.". University Libraries, University of Maryland. Retrieved 07/26/2013
- "Tertiary Information Sources". Old Dominion University -- ODU Libraries. September 2012. Retrieved 20 June 2013.
- "Tertiary sources". James Cook University.
- Søndergaard, T. F.; Andersen, J.; Hjørland, B. (2003). "Documents and the communication of scientific and scholarly information: Revising and updating the UNISIST model". Journal of Documentation 59 (3): 278. doi:10.1108/00220410310472509.