History of retired numbers dates back to Lou Gehrig Day
Which pro sports teams have the most retired numbers?
Yankees Retired Numbers - Who Are The 22 Yankees Who Wore Them
Retired Uniforms by Division: National League East - Beyond the Box Score
Fascinating Aspects About the Retired Uniform Numbers of the Detroit Tigers – Society for American Baseball Research
Retired numbers in Phillies team history Phillies Nation - Your source for Philadelphia Phillies news, opinion, history, rumors, events, and other fun stuff.
What the Yankees' uniform number crunch could cost MLB's managers and coaches - The Athletic
Mets to retire numbers of Darryl Strawberry, Doc Gooden
Tennessee Titans to retire Steve McNair's jersey
Derek Jeter's No. 2, Last of Yankees' Single Digits, to Be Retired - The New York Times
Retired Uniform Numbers in the American League
Retired Uniform Numbers in the National League
Retired Uniforms by Division: National League West - Beyond the Box Score
Scherzer honored with jersey retirement - PowerMizzou