Major League Baseball Umpires Association on X: Working a no

Beyond the grunt: Umpires mic up, and baseball changes a bit - Seattle Sports

The SABR Book of Umpires and Umpiring (Baseball Lives): Gerlach, Larry R., Gerlach, Larry R., Nowlin, Bill, Bingham, Dennis, Levin, Len, Barber, Perry, Edelman, Rob, Higham, Harold R., Vincent, David, Andres, Andy

Umpire Angel Hernandez loses again in lawsuit vs MLB when appeals court refuses to reinstate case

Robot umpires at home plate moving up to Triple-A for 2022

Major League Baseball Umpires Association - Wikipedia

ABS system gets rigorous test at Futures Game

IHSAA baseball: Umpire shortage is cancelling games

An analysis of nearly 4 million pitches shows just how many mistakes umpires make

Testimony - MLB official thought Rob Manfred would nix Angel Hernandez World Series assignment - ESPN