These scholarly sources serve a similar purpose to Wikipedia: providing an introduction to an unfamiliar topic, with suggestions for further reading.
Scholars of religion write books. Lots of those books are still in print form, which makes research in religion a little more challenging when you need to use our digital collection.
My general advice is to use whatever style you're most familiar with to cite your sources until someone tells you not to. Chicago style for citing sources is standard in history and religious studies, so it's not a bad thing to get used to using. I've included a link to a very detailed guide to using it by my colleague, and to the manual of style itself. Learn how to cite a book, a journal article, and something from a website, and that will cover about 80% of what you need to cite at BC.