NFL to consider expanding replay reviews
Opinion: Expanded review necessary to ensure refs don't decide outcomes – The Lantern
Surface stays on the sidelines: Microsoft and NFL expand tech partnership, add Teams tool to deal – GeekWire
An Examination of MLB Play Call Challenges – Society for American Baseball Research
March 11, 1986: NFL Adopts Instant Replay
Upon Further Review: A Brief History of Instant Replay
NFL rule changes: Modified instant replay, more positions allowed to wear single-digit jerseys - The Washington Post
NFL Replay: Why Does It Even Exist?, News, Scores, Highlights, Stats, and Rumors
Yes, the NFL puts microchips in footballs, but they're not ready for prime time on key calls – yet