Should MLB use an automated strike zone in place of umps? “Yes, a thousand percent yes.” – The Denver Post
Will robo umpires be the end of the game as we know it? (SB Nation Reacts) - AZ Snake Pit
Umpire (baseball) - Wikipedia
Red Sox-Rays: Umpires explain why Kevin Kiermaier's hit was a ground-rule double in 13th inning
An analysis of nearly 4 million pitches shows just how many mistakes umpires make
MLB umpire salary: How much do they take home on average?
MLB argues umpire Angel Hernandez's 3 overturned calls in 2018 ALDS cost him World Series spot - ESPN
Eastern League's Matsuda working to become first major league umpire from Japan
Umpire (baseball) - Wikipedia
Commentary: Major-league ump Ed Rapuano backs Pope John Paul II
Major League Baseball umpires: Danger zone ahead?
Ump files racial discrimination suit against MLB
Five Minutes with Gerry Davis - Little League