One thing that makes boxing a unique sport is the many sanctioning organizations that govern the sport. The WBA, WBC, IBF, and WBO are the four major organizations that govern boxing.
A look at the WBA, WBC, IBF, and other boxing organizations
Chart: The Pyramid of Multi-Division Boxing Champions
Boxing titles explained: How do championship belts work?
A look at the WBA, WBC, IBF, and other boxing organizations
Will the IBO be boxing's next major title? - Sports Illustrated
What do the continental and silver boxing belts mean? - Quora
3 Things We Learned From Gervonta Davis Vs Ryan Garcia
What are the major boxing titles? Listing the championship belts
3 Things We Learned From Gervonta Davis Vs Ryan Garcia
Boxing History
Heads Of WBA, WBC, IBF, WBO Meet In Hopes Of Standardizing Title
The Four Belt Era: Boxing's belt problem – The Daily Free Press
Boxing Title Fights - Reference Book about All-times Boxing World
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