Raffles and the ToS

Last topic named "Lottery and the ToS" was deleted, for a good reason probably. This time, can you keep it to a informative minimum of responses? Don't debate, just answer the question if you know the answer. All I'm looking for is information, not anything else.

The question : Is lottery (or gambling) (in-game, with in-game gold) with a non-profit system, against the ToS? If you think so, please indicate where it is written.

Again, I don't want to know if it's wrong/right/stupid, just if you can do it.