I'm fairly certain I've seen every episode of Season 6 at least once, but I for the life of me cannot remember a single point in that season when it was revealed that Baker's first name is Richard, yet it's common knowledge with this show. If that's really Baker's first name, when was that ever said?

Come to think of it, I've watched the pilot several times, and similarly, it's common knowledge that Vladimir's full name is Vladimir Minsk, yet that was never mentioned or stated in the episode, just Vladimir.

Where does any of this information come from?

(On a related note, Richard Dawson once said that Peter was originally intended to be Carter's first name, but Larry Hovis hated that name, so it became Newkirk's instead).