In baseball, the knuckleball is quickly disappearing - The Washington Post

Why are there no knuckleballers in professional baseball anymore? Is it a physiological issue, the difficulty catching a knuckleballer, or something else? - Quora

Tim Wakefield, Red Sox knuckleball pitcher and World Series champ, dies at 57

Knuckleball! (2012) - IMDb

Knuckleball Research

Tim Wakefield and the Glory of the Knuckleball

Pitcher Matt Waldron continues knuckleball transformation as San Antonio Missions open Double-A season

Unpredictable and unmanly: baseball's fear of the knuckleball, Baseball

Shove' the one you're with: Max Scherzer was simply dealing for the Nationals - The Washington Post