If you properly cite material you are quoting, then there is no problem. But you have to follow the rules of citing. This means that after you quote something you have to explain what it is you quotes, cited material never speaks for itself. This also means proper referencing of the book, page, author, publisher, ect.
Also, you can't post the whole rulebook or entries even and claim your just citing it, it has to apply specificly to what you are discussing.
Those are the copyright rules for citing someone else's work.