Wikipedia is a compendium of knowledge published by reliable sources, so all material must be attributable to a reliable published source to be eligible for inclusion. Wikipedia is not the place to publish your ideas, opinions, experiences, or arguments.

Although everything on Wikipedia must be attributable, in practice not all material is attributed. Editors should provide attribution to a reliable source using an inline citation for all quotations, and for any material that is challenged or likely to be challenged, or it may be removed. The burden of evidence lies with the editor wishing to add or retain the material. If a particluar topic has no reliable sources, Wikipedia should not have an article on it.

"Material" as used in this policy includes not only the explicit content, but also its implications. All explicit or implicit points advanced by the way material is selected, combined or presented, must be directly attributable to a reliable source making those points in relation to the article topic.

Wikipedia:Attribution is one of Wikipedia's core content policies. Together with Wikipedia:Neutral point of view, the two determine the type and quality of material that is acceptable in articles; that is, content on Wikipedia must be attributable and written from a neutral point of view. Because the policies are complementary, they should not be interpreted in isolation from one another.

Key principles edit

Wikipedia articles must be based on reliable sources edit

All Wikipedia content material must be attributable (or "verifiable") to reliable sources, and all Wikipedia articles must be based on such sources. Reliable sources are credible published materials with a reliable publication process; their authors are generally regarded as trustworthy or authoritative in relation to the subject at hand. How reliable a source is depends on context. In general, the most reliable sources are books and journals published by universities; mainstream newspapers; and university level textbooks, magazines and journals that are published by known publishing houses. What these have in common is process and approval between document creation and publication. As a rule of thumb, the more people engaged in checking facts, analyzing legal issues, and scrutinizing the writing, the more reliable the publication. Material that is self-published is generally not regarded as reliable, but see below for exceptions. Any unattributed material may be removed, and in biographies of living persons unattributed or poorly sourced contentious material must be removed immediately.

Wikipedia does not publish unattributable material edit

"Unattributable material" (sometimes called "original research" on Wikipedia) refers to material that cannot be attributed to a reliable, published source. This includes unpublished facts, arguments, ideas, statements, and neologisms; and any unpublished analysis or synthesis of published material that appears to advance a position. Material added to articles must be directly and explicitly attributable to reliable sources.

Note the distinction between "unattributed" (also called "unsourced" or "uncited") and "unattributable" material:

  • Unattributed material is not yet attributed to a reliable source, but may be attributable.
  • Unattributable material cannot be attributed to a reliable source, because such a source cannot be found.

The only way to demonstrate that material is not unattributable is to attribute it using an inline citation to reliable sources that directly support it, and to adhere to what those sources say. If the material in question includes an analysis or an argument, the source must make that same analysis or argument in relation to the article topic.

Burden of evidence edit

The burden of evidence lies with the editor who adds or restores material.[1] All quotations and any material challenged or likely to be challenged must be attributed to a reliable, published source using an inline citation. The source should be cited clearly and precisely, with page numbers where appropriate, and must clearly support the material as presented in the article. Drawing inferences from multiple sources to advance a novel position is prohibited, see below.[2] If no reliable third-party sources can be found on a topic, Wikipedia should not have an article on it.

Any material lacking a reliable source directly supporting it may be removed, but how quickly this should happen depends on the material and the overall state of the article. Editors might object if you remove material without giving them time to provide references. It has always been good practice to make reasonable efforts to find sources oneself that support such material, and cite them. Do not leave unattributed or poorly sourced material in an article if it might damage the reputation of living persons or organizations, and do not move it to the talk page.[3]

Sources edit

All Wikipedia material must be attributable (or "verifiable") to published, reliable sources. The following sections describe the identification, evaluation and citation of such sources.

Reliable sources edit

The word "source" as used in Wikipedia has three meanings: the piece of work itself (a document, article, paper, or book), the creator of the work (for example, the writer), and the publisher of the work (for example, The New York Times). All three can affect reliability.

Articles should be based on reliable, third-party (independent), published sources with a reputation for fact-checking and accuracy; this avoids plagiarism, copyright violations, and unverifiable claims being added to articles. Sources should directly support the material as it is presented in an article, and should be appropriate to the claims made.

The appropriateness of any source depends on the context. In general, the best sources have a professional structure in place for checking or analyzing facts, legal issues, evidence, and arguments; as a rule of thumb, the greater the degree of scrutiny given to these issues, the more reliable the source. Academic and peer-reviewed publications are usually the most reliable sources where available, such as in history, medicine, and science, but material from reliable non-academic sources may also be used in these areas, particularly if it appears in respected mainstream publications. Other reliable sources include university-level textbooks, books published by respected publishing houses, magazines, journals, and mainstream newspapers. Electronic media may also be used, subject to the same criteria.

Self-published expert sources are regarded as reliable in limited circumstances (see below). All self-published sources, whether experts or not, are considered reliable as sources on themselves, especially in articles about themselves, subject to certain criteria, though no article should be based primarily on such sources (see below).

Primary, secondary and tertiary sources edit

Wikipedia articles should be based on reliable, published secondary sources and, to a lesser extent, on tertiary sources. Secondary or tertiary sources are needed to establish the topic's notability and to avoid novel interpretations of primary sources, though primary sources are permitted if used carefully. 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.

Appropriate sourcing can be a complicated issue, and these are general rules. Deciding whether primary, secondary or tertiary sources are appropriate on any given occasion is a matter of common sense and good editorial judgment, and should be discussed on article talk pages. For the purposes of this policy, primary, secondary and tertiary sources are defined as follows:[4]

  • Primary sources are very close to an event, often accounts written by people who are directly involved, offering an insider's view of an event, a period of history, a work of art, a political decision, and so on. An account of a traffic accident written by a witness is a primary source of information about the accident; similarly, a scientific paper is a primary source about the experiments performed by the authors. Historical documents such as diaries are primary sources.[5]
Our policy: Primary sources that have been reliably published may be used in Wikipedia, but only with care, because it is easy to misuse them. Any interpretation of primary source material requires a reliable secondary source for that interpretation. A primary source can be used only to make descriptive statements that can be verified by any educated person without specialist knowledge. For example, an article about a novel may cite passages to describe the plot, but any interpretation needs a secondary source. Do not make analytic, synthetic, interpretive, explanatory, or evaluative claims about material found in a primary source. Do not base articles entirely on primary sources. Do not add material from your personal experience, as that would make Wikipedia a primary source of that material.
  • Secondary sources are second-hand accounts, at least one step removed from an event. They rely for their material on primary sources, often making analytic or evaluative claims about them.[6] For example, a review article that analyzes research papers in a field is a secondary source for the research.[7]
Our policy: Wikipedia articles usually rely on material from secondary sources. Articles may include analytic or evaluative claims only if these have been published by a reliable secondary source.
  • Tertiary sources are publications such as encyclopedias or other compendia that mainly summarize secondary sources. Wikipedia is a tertiary source. Many introductory undergraduate-level textbooks are regarded as tertiary sources because they sum up multiple secondary sources.
Our policy: Reliably published 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. Wikipedia articles may not be used as tertiary sources in other Wikipedia articles, but are sometimes used as primary sources in articles about Wikipedia itself.

Newspaper and magazine "blogs" edit

Personal and group blogs are largely not acceptable as sources; see below. Some newspapers host interactive columns that they call blogs; these are acceptable as sources so long as the writers are professionals and the blog is subject to the newspaper's full editorial control. In March 2010, the Press Complaints Commission in the UK ruled that journalists' blogs hosted on the websites of newspapers or magazines are subject to the same standards expected of comment pieces in that organization's print editions.[8] Where a news organization publishes an opinion piece, the author should be identified via in-text attribution (e.g. "Jane Smith has suggested..."). Posts left by readers may never be used as sources.

Using questionable or self-published sources edit

Questionable sources edit

Questionable sources are those with a poor reputation for checking the facts, or with no editorial oversight. Such sources include websites and publications expressing views that are widely acknowledged as extremist, or promotional, or which rely heavily on rumor and personal opinion. Questionable sources should be used only as sources of material on themselves, especially in articles about themselves; see below for the restrictions on using self-published sources in this way. Questionable sources are generally unsuitable for citing contentious claims about third parties.

Self-published sources (online and paper) edit

Anyone can create a website or pay to have a book published, then claim to be an expert in a certain field. For that reason self-published media—including but not limited to books, newsletters, personal websites, open wikis, personal or group blogs, Internet forum postings, and tweets—are largely not acceptable.

Self-published material may in some circumstances be acceptable when produced by an established expert on the topic of the article whose work in the relevant field has previously been published by reliable third-party publications. Caution should be exercised when using such sources: if the information in question is really worth reporting, someone else is likely to have done so. Self-published sources should never be used as third-party sources about living persons, even if the author is a well-known professional researcher or writer: see WP:BLP#Reliable sources.

Self-published and questionable sources as sources on themselves edit

Self-published or questionable sources may be used as sources of information about themselves, especially in articles about themselves, without the requirement that they be published experts in the field, so long as:

  1. the material is not unduly self-serving;
  2. it does not involve claims about third parties;
  3. it does not involve claims about events not directly related to the subject;
  4. there is no reasonable doubt as to its authenticity;
  5. the article is not based primarily on such sources.

Exceptional claims require exceptional sources edit

Certain red flags should prompt editors to examine the sources for a given claim:

  • surprising or apparently important claims that are not widely known;
  • surprising or apparently important reports of historical events not covered by mainstream news media or historiography;
  • reports of a statement by someone that seems out of character, embarrassing, controversial, or against an interest they had previously defended;
  • claims not supported or claims that are contradicted by the prevailing view in the relevant academic community. Be particularly careful when proponents of such claims say there is a conspiracy to silence them.

Exceptional claims should be supported by the best sources, and preferably multiple reliable sources, especially regarding scientific or medical topics, historical events, politically charged issues, and biographies of living people.

Citing Wikipedia or its mirrors edit

Articles on Wikipedia, or on websites that mirror its content, should not be used as sources, because this would amount to self-reference. Similarly, editors should not use sources that present material originating from Wikipedia to support that same material in Wikipedia, as this would create circular sourcing—Wikipedia citing a source that derives its material from Wikipedia. Wikipedia may be cited with caution as a primary source of information on itself, such as in articles about itself.

Citing yourself edit

You may cite your own publications just as you would cite anyone else's, but make sure your material is relevant and that you are regarded as a reliable source for the purposes of Wikipedia. Be cautious about excessive citation of your own work, which may be seen as promotional or a conflict of interest; when in doubt, check on the talk page.

How to cite sources edit

Further information and examples: Wikipedia:Citing sources and Wikipedia:Citations quick reference

Any reader should be able to verify that material added to Wikipedia has already been published by a reliable source. Material that is challenged or likely to be challenged, and quotations, should be accompanied by a clear and precise citation, normally written as a footnote, a Harvard reference, or an embedded link; other methods, including a direct description of the source in the article text, are also acceptable.

Any edit lacking attribution may be removed, and the final burden of evidence lies with the editor wishing to add or retain the material. However, this policy should not be used to cause disruption by removing material for which reliable sources could easily or reasonably be found — except in the case of contentious material about living persons, which must be removed immediately. If you encounter a harmless statement that lacks attribution, you can tag it with the {{fact}} template, or move it to the article's talk page with a comment requesting attribution. If the whole article or an entire section is unattributed, you can use the {{unreferenced}} template. Absurd unattributed claims and unattributable material should be deleted rather than tagged or moved to a talk page.[9]

Source language edit

Because this is the English Wikipedia, English-language sources should be used in preference to non-English ones, except where no English source of equal quality can be found that contains the relevant material. When quoting a source in a different language, provide both the original-language quotation and an English translation, in the text or in a footnote. Translations published by reliable sources are preferred over translations by Wikipedians. When citing a source in a different language, without quotations, the original and its translation should be provided if requested by other editors: this can be added to a footnote, or to the talk page if too long for a footnote. If posting original source material, editors should be careful not to violate copyright; see the fair-use guideline.

Access to sources edit

Attributability, in this context, means that anyone should be able to verify that all material in a Wikipedia article has already been published by a reliable source, as required by this policy. Attributability implies nothing about ease of access to sources: some online sources may require payment, while some print sources may be available only in university libraries. WikiProject Resource Exchange may be able to assist in obtaining copies/excerpts of sources that are not easily accessible.

Reliable sources noticeboard and IRS guideline edit

To discuss the reliability of specific sources, consult the reliable sources noticeboard, which seeks to apply this policy to particular cases. For a guideline discussing the reliability of particular types of sources, see Wikipedia:Identifying reliable sources (IRS). In the case of inconsistency between this policy and the IRS guideline, or any other guideline, the policy has priority.

Requesting a source edit

If you want to request a source for an unattributed statement, consider tagging a sentence with the {{citation needed}} template—write {{cn}} or {{fact}}. Other templates are available here for tagging sections or entire articles. Alternatively, leave a note on the talk page requesting a source, or move the material there. To request verification that a reference supports the text, tag it with {{verification needed}}. Material that fails verification may be tagged with {{failed verification}} or removed. Unattributed or poorly sourced contentious material about living persons should be removed immediately and not tagged or moved to the talk page.

Content material edit

All Wikipedia content material, both explicit and implicit, must be attributable (or "verifiable") to reliable sources and must faithfully reflect what they say, as described below.

Creating attributable content material from reliable sources edit

Collecting and organizing Wikipedia content material from existing sources within the provisions of this and other content policies is fundamental to writing an encyclopedia. The best practice is to write articles by finding the most reliable sources on the topic and summarizing what they say in your own words, with each statement in the article attributable to a source that explicitly supports that statement. Source material should be carefully summarized or rephrased without changing its meaning or implication.

All material in an article must be attributable to reliable sources, and must be attributed to them via inline citation if the material is challenged, likely to be challenged, or quoted. Where material is attributed, the provided references must be cited in context and on topic. Article statements generally should not rely on unclear or inconsistent passages nor on passing comments. Passages open to multiple interpretations should be precisely cited or avoided. A summary of extensive discussion should reflect the conclusions of the source's author(s). Conclusions not evident in the reference are considered unattributable regardless of the type of source. Take care not to go beyond what is expressed in the sources or to use them in ways inconsistent with the intent of the source, such as using material out of context. In short, stick to the sources.

Synthesis of published material that advances a position edit

Do not combine material from multiple sources to reach or imply a conclusion not explicitly stated by any of the sources. If one reliable source says A, and another reliable source says B, do not join A and B together to imply a conclusion C that is not mentioned by any of the sources. This would be a synthesis of attributable material to advance an unattributable position.[10] "A and B, therefore C" is acceptable only if a reliable source has published the same argument in relation to the topic of the article.

  • A simple example of original synthesis:

The UN's stated objective is to maintain international peace and security, but since its creation there have been 160 wars throughout the world.

Although no conclusion is drawn and both parts of the sentence are true, it implies that the UN has failed to maintain world peace. If no reliable source has combined the material in this way, it is unattributable. It would be easy to imply the opposite using the same material, illustrating how material can easily be manipulated when no source is provided:

The UN's stated objective is to maintain international peace and security, and since its creation there have been only 160 wars throughout the world.

  • The following is a more complex example of original synthesis, based on an actual Wikipedia article about a dispute between two authors, here called Smith and Jones. The first paragraph is fine and properly sourced:

Smith claimed that Jones committed plagiarism by copying references from another author's book. Jones responded that it is acceptable scholarly practice to use other people's books to find new references.

Now comes the original synthesis:

If Jones did not consult the original sources, this would be contrary to the practice recommended in the Harvard Writing with Sources manual, which requires citation of the source actually consulted. The Harvard manual does not call violating this rule "plagiarism". Instead, plagiarism is defined as using a source's information, ideas, words, or structure without citing them.

The second paragraph is unattributable because it expresses a Wikipedia editor's opinion that, given the Harvard manual's definition of plagiarism, Jones did not commit it, and we assume there is no reliable source directly supporting that conclusion. To make the second paragraph consistent with this policy, a reliable source would be needed that specifically comments on the Smith and Jones dispute and makes the same point about the Harvard manual and plagiarism. In other words, that precise analysis must have been published by a reliable source in relation to the topic before it can be published in Wikipedia.

See above for advice on how to create attributable content by summarizing sources without violating this policy.

Routine calculations edit

Routine calculations, such as adding numbers, converting units, or calculating a person's age, are considered attributable, provided editors agree that the arithmetic and its application correctly reflect the attributed sources. See here for some conversion templates.

Original images edit

Wikipedia editors are encouraged to take photographs or draw pictures or diagrams and upload them, releasing them under the GFDL or another free license, to illustrate articles. This is welcomed because images generally do not advance unattributable ideas or arguments. Also, because of copyright law in a number of countries and its relationship to the work of building a free encyclopedia, there are relatively few publicly available images we can take and use. Wikipedia editors' pictures fill a needed role.

A disadvantage of allowing original photographs to be uploaded is the possibility of editors using photo manipulation to distort the facts or position being illustrated by the photo. Manipulated images should be prominently noted as such. If they are noted as manipulated, they should be posted to Wikipedia:Images for deletion if the manipulation materially affects the encyclopedic value of the image, or helps advance an unattributable idea or argument.

Images that advance unattributable ideas are not allowed, such as a diagram of a hydrogen atom showing extra particles in the nucleus as theorized by the uploader.

Image captions (also known as "cutlines") are subject to the attributability requirement (and other applicable content policies) no less than statements in the body of the article.

Neutrality edit

Wikipedia content material must be attributable to reliable published sources, but all articles must also adhere to the neutrality policy, fairly representing all majority and significant-minority attributable viewpoints, in rough proportion to the prominence of each view. Tiny-minority views should not be included, except possibly in articles devoted to them, and views not attributable to a reliable published source should not appear anywhere on Wikipedia. Where views are contentious or there is disagreement between sources, they should be identified using in-text attribution: "John Smith argues that X, while Paul Jones maintains that Y," followed by an inline citation.

Living persons edit

In addition to the general attributability requirement, editors must take particular care when writing biographical material about living persons, for legal reasons and in order to be neutral. Remove unattributed or poorly sourced contentious material immediately if it's about a living person, and do not move it to the talk page.[11] This applies to any material related to living persons on any page in any namespace, not just the article space.

See also edit

Notes edit

  1. ^ This is because it is generally much harder to prove that a statement is unattributable than to attribute it.
  2. ^ When there is dispute about whether a piece of text is fully supported by a given source, direct quotes and other relevant details from the source should be provided to other editors as a courtesy.
  3. ^ As Wikipedia co-founder Jimmy Wales has put it: "I can NOT emphasize this enough. There seems to be a terrible bias among some editors that some sort of random speculative 'I heard it somewhere' pseudo information is to be tagged with a 'needs a cite' tag. Wrong. It should be removed, aggressively, unless it can be sourced. This is true of all information, but it is particularly true of negative information about living persons" (Jimmy Wales Zero information is preferred to misleading or false information, WikiEN-l, May 16, 2006, accessed June 11, 2006).
  4. ^ This University of Maryland library page provides typical examples of primary, secondary and tertiary sources.
  5. ^ Further examples include archeological artifacts, census results, video or transcripts of surveillance, public hearings, trials, or interviews; tabulated results of surveys or questionnaires; original philosophical works; religious scripture; and artistic and fictional works such as poems, scripts, screenplays, novels, motion pictures, videos, and television programs. For 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."
  6. ^ University of California, Berkeley library defines "secondary source" as "a work that interprets or analyzes an historical event or phenomenon. It is generally at least one step removed from the event".
  7. ^ The Ithaca College Library compares research articles (primary sources) to review articles (secondary sources).
  8. ^ Plunkett, John. "Rod Liddle censured by the PCC", The Guardian, March 30, 2010.
  9. ^ Wales, Jimmy. "Zero information is preferred to misleading or false information", WikiEN-l, May 16, 2006.
  10. ^ Jimmy Wales has said of synthesized historical theories: "Some who completely understand why Wikipedia ought not create novel theories of physics by citing the results of experiments and so on and synthesizing them into something new, may fail to see how the same thing applies to history." (Wales, Jimmy. "Original research", December 6, 2004)
  11. ^ Wales, Jimmy. "Zero information is preferred to misleading or false information", WikiEN-l, May 19, 2006.