The NCAA doesn't say anything about it, because the NCAA doesn't recognize a national championship in Division I-A football.
The problem with trying to figure out how many national championship any school "really" has is that, for the first half of the history of college football, there's not really any evidence that people thought of "The National Championship" in the same way that we do today. Sometimes the polls were before the bowl games, sometimes afterwards, and the bowl games were treated more as exhibitions than actual games. (I've read that a lot of times the whole team didn't even make the trip.) You will hear old-timers say that winning the SEC was considered to be a lot more important than finishing first in the AP poll. Trying to go back now and apply our own standards in an effort to figure out who the "real" national championship winners were in the 30s and 40s is pretty much a futile exercise.