[bonoboTP]

It's so silly for teachers to say "you are not allowed to cite Wikipedia". It's a cart-before-horse approach, mindless rule-following. The principle in academic writing is that you cite whatever you used for your research. IF you read the Wikipedia article and base some of your conclusions on its synthesis, then you MUST cite Wikipedia, citing the sources of Wikipedia would be misleading IF you don't read those cited sources yourself. It's all about traceability and credit assigment. You can of course cite also what Wikipedia cites but you have to cite Wikipedia if you use claims from there that you didn't actually get from looking at the source cited by Wikipedia.

However! It's also important to teach students how sources differ in quality or "authoritativeness". The problem with citing Wikipedia is not the citing per se but relying on that source. A peer reviewed academic journal is considered more reliable, although no source should be taken as gospel and definitive truth, especially on controversial topics.

You can even cite blog posts, personal letters, and even personal oral communication! The point is to let the reader know where your info comes from. Making students memorize rules like "don't cite Wikipedia" just results in a cargo cult, not actual understanding of critical thinking related to sources.