Keep imperfect instant replay challenge system in case of odious error - Newsday
American football rules - Wikipedia
INSTANT REPLAY in MADDEN OVERDRIVE?! + MASTER LEAKED!
Hawk-Eye NFL Football Operations
NFL Notes: Time to 'start over' but where to begin?
History of Instant Replay
Official to initiate PI replays inside 2 minutes, Hail Marys to be reviewable
The NFL has an instant replay camera problem
NFL refs and instant replay are destroying the league
History of Instant Replay
Eagles 31, 49ers 7: NFC Championship Game instant analysis
Where have all of the NFL points gone?
The NFL has an instant replay camera problem
The History of Instant Replay in the NFL, News, Scores, Highlights, Stats, and Rumors