Gísla saga Súrssonar (Icelandic pronunciation: [ˈcistla ˈsaːɣa ˈsur̥sɔnar̥] , The saga of Gísli the Outlaw) is one of the sagas of Icelanders. It tells the story of Gísli, a tragic hero who must kill one of his brothers-in-law to avenge another brother-in-law. Gisli is forced to stay on the run for thirteen years before he is hunted down and killed. The events depicted in the saga took place between 860 and 980. Manuscripts and dating. Gísla saga survives in thirty-three manuscripts and fragments from the Middle Ages down to the twentieth century.
https://en.wikipedia.org/wiki/G%C3%ADsla_saga