The two orientations used to study knuckle-ball effects. Also

Explaining a fastball's unexpected twist

Basketball Physics: Why Is That Ball Spinning?

PDF) A comparison of Jabulani and Brazuca non-spin aerodynamics

Effect of panel shape of soccer ball on its flight characteristics

John GOFF, Professor of Physics, PhD, Physics

Sensors, Free Full-Text

PDF) A comparison of Jabulani and Brazuca non-spin aerodynamics

Predicting a Baseball's Path

PDF) Physics of knuckleballs

How to Throw Curveball. An Introduction to the Art of the…, by Brent Pourciau

Swing and reverse swing of a cricket ball: laminar separation bubble, secondary vortex and wing-tip-like vortices, Journal of Fluid Mechanics

What are the advantages and disadvantages of using the knuckleball as a primary pitch in baseball? - Quora

SPORTS BALL AERODYNAMICS: EFFECTS OF VELOCITY - TMS

Are all balls used in sports round except for footballs? - Quora

Brazuca x Jabulani: Adidas promete não repetir os problemas da

Sold at Auction: Adidas Jabulani World Cup 2010 official match

Why there won't be a Jabulani-type ball controversy at the 2014

Jabulani - Canada

Pakistani Brazuca has better aerodynamics than Jabulani: NASA