MLB Umpires Missed 34,294 Pitch Calls in 2018. Time for Robo-umps?, BU Today
The Ultimate Guide to How to Become an MLB Umpire? - NISR
Minor League Umpires To Receive Significant Pay Raise In 2022 — College Baseball, MLB Draft, Prospects - Baseball America
The Ultimate Guide to How to Become an MLB Umpire? - NISR
MLB's Umpires. A problematic history, a modern dilemma. — A Historic Take
An Umpire Took One Too Many Foul Balls to the Face. He Invented a Solution. - WSJ
They Call 'Em Like They See 'Em - Twinkie Town
For first-year MLB umpire Chris Segal, 2020 means fewer games, fewer boos - The Washington Post
The umpire on the cusp of a watershed moment for baseball: 'I think she's going to do it' - The Athletic
MLB makes history by naming its first black and Latino-born umpire crew chiefs