MLB umpire Joe West, at last, is retiring - Bleed Cubbie Blue
For Volunteer Umpires, Little League World Series in the Pinnacle - The New York Times
Umpire: What Is It? and How to Become One?
Robot Umpires Strike Zone: It's Not as Simple as You ThinkBaseball Prospectus
Plainfield Independent Umpire training
Robot umpires: New baseball innovation points towards society's demise - Sports Illustrated
Bryce Harper ejected: What went through the Phillies' star's head?
Two local umpires look ahead to summer assignments, grind for future success, Sports
3 Easy Ways to Become an Umpire - wikiHow Fitness