For scholarly research, you would normally use wikipedia as a starting point and move on to work with other primary and secondary sources that it signposts. It would then be those subsequent sources that you evaluate and cite in your work.
However, there may be occasions when it is appropriate for you to cite a Wikipedia article. For example, in a skills module you may well be asked to critique a wikipedia article as a research resource and in that case you would need to accurately cite the article you are critiquing.
Click on the Cite this page link on the left hand side of the page
This provides ready referencing information in various styles that you can use in your own footnotes, reference lists and bibliographies.