Question: David Overstreet and Barry Switzer worked together for which university?
Context: David Arthur Overstreet (September 20, 1958 – June 24, 1984) was a running back in the Canadian Football League and National Football League.  He played for coach Barry Switzer and the Oklahoma Sooners as a halfback out of the wishbone offense. Barry Layne Switzer (born October 5, 1937) is a former American football player and coach.  He served for 16 years as head football coach at the University of Oklahoma and four years as head coach for the Dallas Cowboys of the National Football League (NFL).  He helped the Cowboys win Super Bowl XXX against the Pittsburgh Steelers.  He has one of the highest winning percentages of any college football coach in history, and is one of only three head coaches to win both a college football national championship and a Super Bowl, the others being Jimmy Johnson and Pete Carroll. The Barry Switzer Center, on the University of Oklahoma campus in Norman, Oklahoma, houses football offices, the football locker room, equipment room, the Siegfried Strength and Conditioning Complex, the Freede Sports Medicine Facility and the Touchdown Club Legends Lobby.  The Center is located at the south end of the Gaylord Family Oklahoma Memorial Stadium.  The Barry Switzer Center, dedicated on April 24, 1999, was named after OU’s all-time winningest head football coach.  During Summer 2015 the Switzer Center was demolished as part of the expansion of Gaylord Family Oklahoma Memorial Stadium.  In Barry Switzer’s 16 seasons as the Oklahoma Sooners head football coach, the team won three national championships, 12 Big Eight Conference championships and eight bowl games in 13 appearances. The 1978 Oklahoma Sooners football team represented the University of Oklahoma in the college football 1978 NCAA Division I-A season.  Oklahoma Sooners football participated in the former Big Eight Conference at that time and played its home games in Oklahoma Memorial Stadium where it has played its home games since 1923.  The team posted an 11–1 overall record and a 6–1 conference record to earn a share of the conference title under head coach Barry Switzer.  This was Switzer's sixth conference title in six seasons since taking the helm in 1973. The 1984 Oklahoma Sooners football team represented the University of Oklahoma in the college football 1984 NCAA Division I-A season.  Oklahoma Sooners football participated in the former Big Eight Conference at that time and played its home games in Gaylord Family Oklahoma Memorial Stadium where it has played its home games since 1923.  The team posted a 9–2–1 overall record and a 6–1 conference record to earn a share of the Conference title under head coach Barry Switzer who took the helm in 1973.  This was Switzer's ninth conference title in twelve seasons. The 1976 Oklahoma Sooners football team represented the University of Oklahoma in the 1976 NCAA Division I football season.  Oklahoma was a member of the Big Eight Conference and played its home games in Oklahoma Memorial Stadium, where it has played its home games since 1923.  The team posted a 9–2–1 overall record and a 5–2–0 conference record to earn a share of the Conference title under head coach Barry Switzer who took the helm in 1973.  This was Switzer's fourth conference title in four seasons. The Oklahoma Sooners football program is a college football team that represents the University of Oklahoma.  The team has had 22 head coaches since organized football began in 1895.  The Sooners have played in more than 1,200 games in its 121 seasons.  In those seasons, eight coaches have led the Sooners to postseason bowl games: Tom Stidham, Jim Tatum, Bud Wilkinson, Gomer Jones, Chuck Fairbanks, Barry Switzer, Gary Gibbs and Bob Stoops.  Eight coaches have won conference championships with the Sooners: Bennie Owen, Stidham, Dewey Luster, Tatum, Wilkinson, Fairbanks, Switzer and Stoops.  Wilkinson, Switzer and Stoops have also won national championships with the Sooners.  Stoops is the all-time leader in games coached and won, Owen is the all-time leader in years coached, while Switzer is the all-time leader in winning percentage.  John Harts is, in terms of winning percentage, the worst coach the Sooners have had as he lost the only game he coached.  John Blake has the lowest winning percentage of those who have coached more than one game with .353 in his 34 games. The 1973 Oklahoma Sooners football team represented the University of Oklahoma in the 1973 NCAA Division I football season.  Oklahoma participated as members of the Big Eight Conference and played its home games in Gaylord Family Oklahoma Memorial Stadium where it has played its home games since 1923.  The team posted a 10–0–1 overall record and a 7–0 conference record to earn the Conference outright title under first-year head coach Barry Switzer.  This would be the first of eight consecutive Big Eight Conference championships for the Sooners with Switzer as head coach. The 1977 Oklahoma Sooners football team represented the University of Oklahoma in the 1977 NCAA Division I football season.  Oklahoma was a member of the Big Eight Conference and played its home games in Oklahoma Memorial Stadium, where it has played its home games since 1923.  The team posted a 10–2 overall record and a 7–0 conference record to earn the Conference title under head coach Barry Switzer who took the helm in 1973.  This was Switzer's fifth conference title and third undefeated conference record in five seasons. The 1979 Oklahoma Sooners football team represented the University of Oklahoma in the college football 1979 NCAA Division I-A season.  Oklahoma Sooners football participated in the former Big Eight Conference at that time and played its home games in Gaylord Family Oklahoma Memorial Stadium where it has played its home games since 1923.  The team posted an 11–1 overall record and a 7–0 conference record to earn the Conference title outright under head coach Barry Switzer who took the helm in 1973.  This was Switzer's seventh conference title and fourth undefeated conference record in seven seasons.
Answer: University of Oklahoma