From entry C4.5 in glossary Artificial Intelligence: humans at the heart of algorithms
C4.5 is one of the most well known variants of Quinlan's ID3 decision tree learning algorithm. C4.5 has a number of variations from basic ID3 including the use of normalised information gain for non-binary node decisions.
Used in Chap. 8: page 122
Links:
Wikipedia: C4.5 algorithm- YouTube: C4.5 Decision Tree algorithm