Is there canon evidence that Yuri's mom is named Origa Petrov? So far, what I've seen calls her simply オリガ (Origa): end credits for ep. 16 and Hero Gossips pp. 56 and 79. I've poked around a bit on the net, including checking her seiyuu's credits, and found no more. She's not even listed among the characters at
http://www.tigerandbunny.net/tv/character/index.html.
Granted, it seems unlikely Yuri and his mom would not share a last name, but something definitive would make me happier. Is it out there?
ETA: Didn't realize I was unclear. Her first name isn't in question, as far as I'm concerned. But is there evidence that her last name is Petrov? I do appreciate the responses!