A Sport Without Referees? It's the Ultimate Debate - The New York

Episode 136, The Rant: Carl Small – Referee Rant

Rugby World Cup: The controversial referee calls of the France-South Africa match

Will College Athletes Make Money? Here's Where the Debate Stands. - The New York Times

Sludge Output: September 2016

Ultimate (sport) - Wikipedia

Cristiano Ronaldo vs Lionel Messi: Who is better and is the GOAT in football? The stats head-to-head showdown

History of Instant Replay

The Observer

Steph Curry and Sabrina Ionescu to settle debate over basketball's best three-point shooter at All-Star Weekend

Ex-Premier League referee Mark Clattenburg 'forced to flee Egypt' after series of attacks - Mirror Online