Wikipedia:Scientific citation guidelines

Source: Wikipedia, the free encyclopedia.

The no original research and verifiability policies are of paramount importance to Wikipedia. Inline citations, which link specific reliable sources with specific pieces of information in the article, provide practical support for these policies by making it easier to check the article content.

This page applies the advice in the policies, and in the citing sources guideline, to referencing science and mathematics articles. The goal is to achieve a reasonable balance between ease of verification, readability and editability. This page also describes some sensible guidelines for dealing with issues that are specific to writing Wikipedia articles (compared to writing for the academic press).

Do not change any article's established citation style without discussing it first.

Uncontroversial knowledge

Some statements are uncontroversial and widely known among people familiar with a discipline. Such facts may be taught in university courses, found in textbooks, or contained in multiple references in the research literature (most importantly in review articles). Some examples are:

These statements are not common knowledge, but the first should be known to anyone with an undergraduate background in physics, the second to anyone knowledgeable about condensed matter physics, and the third to anyone knowledgeable about string theory.

The verifiability criteria require that such statements be sourced so that in principle anyone can verify them. However, in many articles it is cumbersome to provide an in-line reference for every statement. In addition, such dense referencing can obscure the logical interdependence of statements. Therefore, in sections or articles that present well-known and uncontroversial information – information that is readily available in most common and obvious books on the subject – it is acceptable to give an inline citation for one or two authoritative sources (and possibly a more accessible source, if one is available) in such a way as to indicate that these sources can be checked to verify statements for which no other in-line citation is provided. These inline citations are often inserted either after the first sentence of a paragraph or after the last sentence of the paragraph; a single convention should be chosen for each article.

For example, from aldol reaction:

The aldol reaction is an important

α,β-unsaturated ketone
(or aldehyde).

The enol or enolate is itself generated from a

carbonyl compound, often an aldehyde or ketone, using acid or base. If the enol or enolate is formed in situ
, the process can be considered as an acid or base-catalyzed reaction of one carbonyl compound with another. This may involve one aldehyde or ketone reacting with itself. Alternatively two different carbonyl compounds may be used, in which case the reaction is known as a crossed aldol reaction. In the scheme shown, the enol or enolate of a methyl ketone reacts with an aldehyde.

References

Five references are provided early on: two textbooks, a specialized monograph on aldol reactions, and two review articles. Most readers would assume that the bulk of the statements in the comparatively short Wikipedia article could be verified by checking any of these references, and so it may only be necessary to provide additional in-line references for controversial statements, for recent discoveries that are not covered in the standard references, for historical and academic attribution, and for verifying more specialized statements or subsections.

When quoting widely known numbers such as the

WP:V
states that if an editor requests that a particular statement be sourced, that request should be fulfilled. In this case, it may be advisable to add an in-line citation if this would prevent future confusion. However, if the statement is easily found in the principal references already given in the article, a citation may instead be provided on the article's talk page.

Articles without in-line references

Sometimes, short articles (including many stubs) provide a list of references without any inline citations. This can satisfy the sourcing policies when the entire contents of the article can be verified from the sources listed. An example of a very short article covered by

general references is provided by the linked revision of "low basis theorem
".

As an article matures to include more than a few sentences, inline citations are added to make it clear which material in the article can be verified by which source. If a few general references cover the bulk of an article, consider using the technique described in the section Uncontroversial knowledge above. This can be done regardless of article length.

Some material, including direct quotations, contentious material about living people, and any material whose verifiability has been challenged, should always be accompanied by an inline citation, regardless of the length of the article. For more information on these special cases, see

Wikipedia:Biographies of living people
.

Citation format

Since Wikipedia

MathSciNet}} templates may prove useful for creating these database links in free-form citations, or such links can be automatically generated when using the {{citation}}, {{cite book}} or {{cite journal
}} templates using the corresponding parameters.

For some topics the bibliography available may address different audiences, e.g. undergraduate vs. graduate, or levels or rigor, e.g. statistics textbooks for social scientists vs. those addressed to mathematicians. When the audience of a text in the further reading section is not self-evident, it may be useful to annotate it as discussed at

WP:FURTHER
.

Examples, derivations, and restatements

Wikipedia is neither a textbook nor a journal. Nonetheless, in mathematics and the mathematical sciences, it is frequently helpful to quote theorems, include simple derivations, and provide illustrative examples. For reasons of notation, clarity, consistency, or simplicity it is often necessary to state things in a slightly different way than they are stated in the references, to provide a different derivation, or to provide an example. This is standard practice in journals, and does not make any claim of novelty.

copyright
law, unless the source has a free license.

Wikipedia's no-original-research policy allows

WMAP collaboration quotes values for h and Ωbh2.[2]
The values quoted in the article are more useful for non-experts. Anyone who looks at the WMAP paper, and has a basic knowledge of error analyses, will understand how to go from one to the other.

If a calculation, although routine, takes more than one or two steps, it may be helpful to present the details of the calculation in a note to the text. For an example, see the detailed calculation in the article on Methane clathrate giving a derivation of the statement in the article's lead that one liter of methane clathrate solid at STP contains, on average, 168 liters of methane gas.

Attribution

Wikipedia's no original research policy requires that we make it clear assertions do not originate with Wikipedia's editors. This is achieved by providing sources for the material in Wikipedia articles. It is also important, however, for our articles to clearly indicate the person who first discovered an astronomical object, first proved a theorem, first performed an experiment, or was otherwise responsible for the idea being discussed. The process of giving credit to the original discoverer will be called attribution here.

Articles should provide attribution for experiments, theorems, astronomical objects, and similar topics, when the original discoverer is known. Many editors prefer to supply the original source for an idea when providing this attribution, for example:

When the original reference is not suitable as an introduction to the idea, either because it is outdated or because it contains serious errors, it is helpful to note this in an annotation:

  • Beginning with observations in 1912,
    spiral nebulae had considerable redshifts.[5]

Numerical data can also be attributed to the person or group that obtained it. For example, from the neutrino article:

The strongest upper limit on the masses of neutrinos comes from
electron volts.[6]

This provides attribution for academic and historical purposes, and also makes it clear how readers can understand where a number comes from. This not only makes Wikipedia a more convenient resource for readers, but makes it easier to update when better data become available.

A related issue is the attribution of eponyms (terms derived from people's names) such as:

  • ...the Michelson–Morley experiment[7]...
  • ...the Sunyaev–Zel'dovich effect[8]...
  • ...the Green–Schwarz anomaly cancellation mechanism[9]...
  • ...the αβγ neutron capture theory[10]...
  • ...the Kaluza–Klein theory of dimensional reduction[11][12][13]...

If Wikipedia has an article about an eponymous topic – such as

– then editors of this article should, if feasible, explain why the names are attached to the result or experiment. To this end, editors of these articles should consider researching and citing the original papers, even if those papers were not originally used as sources in writing the article. However, articles that only link to an eponymous article might not cite the original papers, depending on context. In this case, a reader looking for a reference may easily click the article link to find it.

See also

Notes

  1. ^ See Manifold Destiny for a possible counterexample.
  2. ^ D. N. Spergel; et al. (WMAP collaboration) (2013). "Bibliography of WMAP Science Team Publications".
  3. .
  4. .. This paper calculates the structure of the group of smooth structures on an n-sphere for n > 4.
  5. Lowell Observatory Bulletin, pp.2.56–2.57 [1]. His article entitled "The radial velocity of the Andromeda Nebula" reports making the first Doppler measurement on September 17, 1912. In his report Slipher writes: "The magnitude of this velocity, which is the greatest hitherto observed, raises the question whether the velocity-like displacement might not be due to some other cause, but I believe we have at present no other interpretation for it." Three years later, in the journal Popular Astronomy, Vol. 23, pp. 21–24 [2], Slipher wrote a review entitled "Spectrographic Observations of Nebulae". In it he states, "The early discovery that the great Andromeda spiral had the quite exceptional velocity of −300 km(/s) showed the means then available, capable of investigating not only the spectra of the spirals but their velocities as well." Slipher reported the velocities for 15 spiral nebulae spread across the entire celestial sphere
    , all but three having observable "positive" (that is recessional) velocities.
  6. .
  7. .
  8. .
  9. .
  10. .
  11. ^ Nordström, Gunnar (1914). "Uber die Möglichkeit, das elektromagnetische Feld und das Gravitationsfeld zu vereinigen" [On the possibility of a unification of the electromagnetic and gravitational fields] (PDF). Physikalische Zeitschrift. 15: 504–506.
  12. ^ Kaluza, Theodor (1921). "On the problem of unity in physics". Sitzungsberichte der Preussischen Akademie der Wissenschaften: 966–972.
  13. .

References