Question: Hardy Brown is one of only two men to play in the NFL, AAFC and AFL, but which Oklahoma college did he play football for?

<P0-S0> Otto Everett Graham Jr. (December 6, 1921 – December 17, 2003) was an American football quarterback who played for the Cleveland Browns in the All-America Football Conference (AAFC) and National Football League (NFL). <P0-S1>  Graham is regarded by critics as one of the most dominant players of his era, having taken the Browns to league championship games every year between 1946 and 1955, winning seven of them. <P0-S2>  With Graham at quarterback, the Browns posted a record of 114 wins, 20 losses, and four ties, including a 9–3 win–loss record in the playoffs. <P0-S3>  While most of Graham's statistical records have been surpassed in the modern era, he still holds the NFL record for career average yards gained per pass attempt, with 8.98. <P0-S4>  He also holds the record for the highest career winning percentage for an NFL starting quarterback, at 0.814. <P0-S5>  Long-time New York Yankees owner George Steinbrenner, a friend of Graham's, once called him "as great of a quarterback as there ever was." <P0-S6>  He is also known for being one of only two people (the other being Gene Conley) to win championships in two of the four major North American sports—1946 NBL (became NBA) and AAFC championship, plus three more AAFC and three NFL championships. <SEP> <P1-S0> Hardy Brown (May 8, 1924 – November 8, 1991) was an American football linebacker in the National Football League (NFL), All-America Football Conference (AAFC), and the American Football League (AFL). <P1-S1>  He played college football at the University of Tulsa and then professionally for the San Francisco 49ers, Washington Redskins, and the Denver Broncos. <P1-S2>  He was one of only two men who played in the All-America Football Conference, the National Football League, and the American Football League (the other was Ben Agajanian). <SEP> <P2-S0> Forrest Porter "Chubby" Grigg, Jr. (January 10, 1926 – October 10, 1983) was an American football tackle who played seven seasons in the All-America Football Conference (AAFC) and National Football League (NFL) in the 1940s and 1950s. <P2-S1>  Grigg grew up in Texas and attended the University of Tulsa in Oklahoma. <P2-S2>  After graduating from college, he joined the AAFC's Buffalo Bisons, where he played for a year. <P2-S3>  Grigg was then sent to the Chicago Rockets in 1947, but stayed only one season before joining the Cleveland Browns in 1948. <P2-S4>  The Browns won all of their games and the AAFC championship that season. <P2-S5>  Cleveland again won the AAFC championship in 1949 before the league dissolved and the Browns were absorbed by the more established NFL. <P2-S6>  Grigg continued to play for the Browns in 1950 and 1951. <P2-S7>  The team won the NFL championship in 1950, and reached the title game but lost it the following year. <P2-S8>  Grigg spent a final season with the Dallas Texans before retiring from football. <SEP> <P3-S0> The University of Tulsa (TU) is a private research university located in Tulsa, Oklahoma, United States. <P3-S1>  The university is renowned for its programs in law, English, computer science, natural sciences, psychology, and engineering. <P3-S2>  Its faculty includes prominent scholars, scientists, and writers, including Russian dissident poet Yevgeny Yevtushenko, political scientist Robert Donaldson and others. <P3-S3>  The university has a historic affiliation with the Presbyterian Church and the campus's architectural style is predominantly Collegiate Gothic.