Why did the Phillies retire Chuck Klein's jersey instead of his number? - Quora
Dick Allen, 78, Dies; Baseball Slugger Withstood Bigotry - The New York Times
Column: Meet Ray Lamb, the last Dodger to wear Jackie Robinson's No. 42 — by mistake - Los Angeles Times
Phillies to retire Dick Allen's No. 15 during 2020 MLB season
Dick Allen: the Life and Times of a Baseball Immortal — William C. Kashatus
Phillies' Dick Allen giveaway is bigger than a bobblehead
Chicago Tribune
Phillies Immortalize Number 15 in Honor of Dick Allen
Dick Allen Hall of Fame: Phillies to retire Dick Allen's #15