Question: Which basketball player had his jersey retired by both the Baltimore Bullets and New York Knicks, and averaged a team high 20.7 points for his team during the 1975-76 NBA season?
Sentence (from "1975–76 New York Knicks season"): The 1975–76 New York Knicks season was the 30th season for the team in the National Basketball Association (NBA).
Relevant evidence: No