NFL has produced memorable Christmas day games, Etvarsity
Opinion My Culture Is Not Super Bowl Entertainment - The New York Times
NFL on Christmas Day: Some of the most memorable games - The San Diego Union-Tribune
Dolphins History: Games Played On Christmas Day
Today in Pro Football History: 1971: Dolphins Defeat Chiefs in Longest NFL Game
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Dolphins and Chiefs played longest game in NFL history on Christmas 1971
On This Date 1971: The Longest Game Ever Played – Kansas City Chiefs v Miami Dolphins