What are some good, free encyclopedias which might be acceptable for an economics student to cite during an introduction to an essay?

Hopefully this post is okay. I'm compiling a list of resources (newspapers/open access statistical databases/encyclopedias/etc) for students to be able use or at least, learn more about economics. I am hoping that this sub might have some recommendations.

note: economics is the focus, but these can be from the perspective of history/business/general/sociology/philosophy/etc. So long as economics is considered.

Thanks 🙂