Reference to real people?

Ok, right now I’m trying to get Effingomancy sorted out, but after that I have another idea for a class. I was thinking that it could be interesting to have a school that was more friendly to each other than other adepts, so my idea is basically a class so obsessed with unity that whenever two of them come close to each other, both of their world views will shift slightly so they are perfectly in line, so they generally form cult-like groups. I’m thinking of calling it Unimancy.

My question is this: Is it ok to include reference to a real person in the “What you’ve heard” section? I was thinking of saying that L. Ron Hubbard is largely believed to have been the greatest Unimancer of all time, and contrary to what everyone’s heard he actually died as a result of a failed attempt to use five or six major charges in a single spell to enslave all of humanity.