The basic requirement for a topic to have its own article is: significant coverage in reliable sources that are independent of the subject.

• Significant coverage is more than a trivial mention, though it doesn’t have to be the core focus of the book or article you cite. On the other hand, it should be more than a single mention or single line of text.
• Reliable sources generally means that coverage comes from secondary sources from reputable publishers. The book, journal article, or other sources you reference should have a reputation for accuracy and fact-checking. Those sources don’t have to be in English, and they don’t have to be online.
• Independent of the subject means the publisher doesn't have a stake in presenting a biased point of view (either positive or negative). For example, self-publicity, advertising, self-published material by the subject of your article, autobiographies, and press releases are not considered independent.