http://en.wikipedia.org/wiki/Wikipedia:Primary_Secondary_and_Tertiary_Sources
http://www.dvc.edu/library/libweb/primary_and_secondary_sources.htm
http://en.wikipedia.org/wiki/Wikipedia:Scientific_standards
Proposed Changes to conform PSTS with V
Primary, secondary, and tertiary sources
For the purposes of Wikipedia policies and guidelines, primary, secondary, and tertiary sources are defined as follows:[1]
- Primary sources are sources very close to the origin of a particular topic or event. An eyewitness account of a traffic accident is an example of a primary source. Other examples include archeological artifacts; photographs; videos; historical documents such as diaries, census results, maps, or transcripts of surveillance, public hearings, trials, or interviews; untabulated results of surveys or questionnaires; written or recorded notes of laboratory and field research, experiments or observations which have not been published in a peer reviewed source,
experimental results by the person(s) actually involved in the research; original philosophical works, religious scripture, administrative documents, patents, and artistic and fictional works such as poems, scripts, screenplays, novels, motion pictures, videos, and television programs.[2]
- Secondary sources are accounts at least one step removed from an event.[3] Secondary sources may draw on primary sources and other secondary sources to create a general overview; or to make analytic or synthetic claims.[4][5]
- Tertiary sources are publications such as encyclopedias or other compendia that sum up secondary and primary sources. For example, Wikipedia itself is a tertiary source. Many introductory textbooks may also be considered tertiary to the extent that they sum up multiple primary and secondary sources.
Wikipedia articles should rely on reliable, published secondary sources. All interpretive claims, analyses, or synthetic claims about primary sources must be referenced to a secondary source, rather than original analysis of the primary-source material by Wikipedia editors.
Primary sources that have been published by a reliable source may be used in Wikipedia, but only with care, because it is easy to misuse them. For that reason, anyone—without specialist knowledge—who reads the primary source should be able to verify that the Wikipedia passage agrees with the primary source. Any interpretation of primary source material requires a reliable secondary source for that interpretation. To the extent that part of an article relies on a primary source, it should:
- only make descriptive claims about the information found in the primary source, the accuracy and applicability of which is easily verifiable by any reasonable, educated person without specialist knowledge, and
- make no analytic, synthetic, interpretive, explanatory, or evaluative claims about the information found in the primary source.
Unsourced material obtained from a Wikipedian's personal experience, such as an unpublished eyewitness account, should not be added to articles. It would violate both this policy and Verifiability, and would cause Wikipedia to become a primary source for that material.
Tertiary sources can be helpful in providing broad summaries of topics that involve many primary and secondary sources. Some tertiary sources may be more reliable than others, and within any given tertiary source, some articles may be more reliable than others. WP:Verifiability#Reliable sources describes some criteria for assessing reliability of sources.
Appropriate sourcing can be a complicated issue, and these are general rules. Deciding whether primary or secondary sources are more suitable on any given occasion is a matter of common sense and good editorial judgment, and should be discussed on article talk pages.
Various professional fields treat the distinction between primary and secondary sources in differing fashions. Some fields and references also further distinguish between secondary and tertiary sources. Primary, secondary and tertiary sources are broadly defined here for the purposes of Wikipedia.
Definitions of primary sources:
- The University of Nevada, Reno Libraries define primary sources as providing "an inside view of a particular event". They offer as examples: original documents, such as autobiographies, diaries, e-mail, interviews, letters, minutes, news film footage, official records, photographs, raw research data, and speeches; creative works, such as art, drama, films, music, novels, poetry; and relics or artifacts, such as buildings, clothing, DNA, furniture, jewelry, pottery.
- The University of California, Berkeley library offers this definition: "Primary sources enable the researcher to get as close as possible to what actually happened during an historical event or time period. Primary sources 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) and they reflect the individual viewpoint of a participant or observer."
The National History Day website states simply that: "Secondary sources are works of synthesis and interpretation based upon primary sources and the work of other authors."