I propose adding the following paragraph, which was largely adapted from a summarization of EN:WP:FRINGE, to this page:
Fringe theories are ideas about a subject that most people who know a lot about that subject would strongly disagree with. Some examples of fringe theories are conspiracy theories and ideas about science that do not have much scientific support. Books and websites that promote fringe theories are usually not considered reliable sources, unless they are being used in an article about those fringe theories. For example, the Simple English Wikipedia has an article about the Flat Earth Society, which claims that the Earth is flat, but the Flat Earth Society's website is not used as a source in the article about the Earth, because it is not considered to be a reliable source. For more information, see en:WP:FRINGE on the English Wikipedia. Kansan (talk) 19:49, 20 April 2010 (UTC)
Reliable sources in science need to be 1. Reliable 2. Secondary.
Reliable: published in a reputable journal (eg Nature, Science...) or (if a book), by a reputable scientist and a reputable publisher. This is because reputable publishers employ qualified readers to critique manuscripts, and have a reputation to uphold.
Websites are reputable if (and only if) they have independent editorial supervision. So a website of the University of California at Berkeley which supports a course is reliable because it has the particular department's supervision behind it.
Secondary: A primary source is one which announces an original finding or opinion of some kind. Generally (there may be exceptions) such papers are too specialised for our purposes. They may need to be interpreted by an expert in the field. Secondary sources are surveys and interpretations by experts in the particular field. Reviews and surveys in Nature and similar journals; university-level textbooks, semi-popular accounts if written by experts (eg Einstein & Infield's Theory of relativity; Mayr's What evolution is).
Tertiary sources are such as articles in the press, most books for children, popular books by authors who are not experts. They are not suitable for references in scientific topics because their reliability is open to question.
A good source will combine both reliability and appropriate breadth. So, a leading encyclopedia has articles by renowned experts and supervised by an editorial team. That makes it a suitable source for reference in one of our scientific topics. Any reference to a website which does not have a similar backing is open to question.
These guidelines are written with science in mind, but would probably apply to many other scholarly areas.
Macdonald-ross (talk) 05:03, 21 April 2010 (UTC)
This is almost always interpreted to mean that no alternative media outlet is a WP:RS. ZeroHedge, for instance, is a frequently cited, and AFAIK well reputed alternative media outlet. Wisdomtooth 20:05, 14 December 2017
An article I am looking at makes a certain claim with a reference provided. The problem is it is not a web reference, so I cannot see it. How can I check that this claim is referenced in a reliable source? How can I check what is in the source? Thank in advance, Ottawahitech (talk) 16:56, 19 December 2017 (UTC) Please ping me
Regarding What kind of sources should I avoid? / Sources linked to the subject ("sources which are written by someone who represents or is the subject") ... What about, conversely, sources that are actively hostile to (possibly in competition with) the subject?— Preceding unsigned comment added by 50.73.98.161 (talk • contribs) 18:10, 22 March 2021 (UTC)