Super Bowl, History, Appearances, Results, & Facts
Most Super Bowl appearances by team
NFL Championships History: Has a team ever switched from NFC to AFC?
NFL Team Values Ranking List –
NFL-National Football League Record Manual 1976-spiral bound-player-team info-VG: Very Good Softcover/Paperback (1976)
NFL Rivalries: What is the oldest rivalry in the NFL History?
NFL Record & Fact Book 2012: The Official National Football League Record and Fact Book - Editors At The NFL: 9781603209151 - AbeBooks
National Football League - Wikipedia