User:Vassyana/sources

Reliable sources
Any material that is challenged or likely to be challenged must be supported by a reliable source. "Original research" is a claim for which no reliable source can be found. Producing a reliable published source that advances the same claim taken in context is the only way to disprove original research. If there is a source, but the source or claim is disputed, that is not original research but rather of a question of reliable sourcing or undue weight.

Reliable secondary sources
Secondary sources draw on research and references to make interpretive, analytical, or synthetic claims, or create a general overview. Publications such as encyclopedias are also considered a type of secondary source. Notably, articles signed by experts in Encyclopædia Britannica, and encyclopedias of similar quality, may be regarded as reliable secondary sources. Unsigned articles can be less reliable, but they may be used so long as the encyclopedia is of a generally high quality. Secondary sources are preferable because they generally provide analysis, offer a more independent view and provide a broader context for the subject.

Reliable secondary sources should be the principle reference material for Wikipedia articles. These sources are up-to-date, written purposefully to inform about the subject they are being cited for, and released by a publisher with a reputation for fact-checking and accuracy. Examples of such references would be recent post-secondary textbooks, a peer-reviewed paper published in a reputable journal, or a contemporary work released by a reliable publisher. Care should be taken to avoid undue weight and ensure the information cited is used in context.

Auxiliary sources
Auxiliary sources should only be used with care, or in context as used in reliable secondary sources. References from questionable, historical and "raw" sources are examples of auxiliary sources. Examples include notable conspiracy theory websites, Bede's History of England and transcripts of the Nixon tapes. Primary sources are usually considered auxiliary sources. A reliable secondary source from one article may be treated as an auxiliary source in another, because the focus has changed. For example, a book by a notable historian is a reliable secondary source for the events it covers, but it would be considered an auxiliary source in the article about the historian. Generally, any source that does not qualify as a reliable secondary source is grouped in this category. The use of these raw, first-hand, or out-of-date sources lends itself to original research, and thus should only be used with caution.

Using auxiliary sources
Articles should usually rely on reliable secondary sources, but there are some occasions and exceptions when auxiliary sources may prove useful. Some of these sources may be particularly reliable and helpful in presenting a complete encyclopedic article, such as census data. Some auxiliary references may also be useful for providing supporting facts, figures or limited quotations to accompany claims and analysis from reliable secondary sources. However, serious care should be taken to avoid presenting a claim or interpretation, explicit or implied, differing from the reliable references cited. Editors should use discretion and consensus to identify such circumstances. An article, or a section of an article, that relies on an auxiliary source should (1) only report what the source states, the accuracy of which is easily verifiable by any reasonable, educated person without specialist knowledge, and (2) make no analytic, synthetic, interpretive, explanatory, or evaluative claims. Contributors drawing on auxiliary sources should be careful to comply with both conditions. Of course, auxiliary sources may be used freely as they are used in reliable publications. In that instance, an editor would be relying on a reliable secondary reference to present, analyze and/or interpret an auxiliary source.