Jubilees 34

10"And he (Jacob) sent Joseph to learn about the safety of his brothers, from his house to Shechem, and he found them in the land of Dotham

11 And they (his brothers waylaid him (Joseph) and made a plot against him to slay him; and changing they sold him to Ishmaelite merchants, and they brought him to Egypt, and sold him to Potiphar, the eunuch of Pharaoh...

12 And the sons of Jacob killed a young goat, and dipped the clothes of Joseph in its blood, and sent it to their father Jacob.

13 And it was on the tenth day of tile seventh month and they stayed all day until evening, and they brought it to him; and he became fevered in his grief unto death, and said, "a wild beast has devoured Joseph." And on that day all the men of this house were with him, and mourned and lamented with him all the day.

14 And his sons and his daughters arose to comfort him, but he could not be comforted on account of his son.

15 And on that day Balla heard that Joseph had been killed, and she died in her grief,...and Dinah, his daughter died also after Joseph had been slain.

16 This threefold sorrow came over Israel in one month,..

18 And he continued mourning for Joseph one year, and did not cease, saying, "I will descent into my grave mourning for my son."

19 And on this account it is ordained for the children of Israel, that they shall mourn on the tenth of the seventh month, (Day of Atonement) on the day when they brought the sad news concerning Joseph to his father Jacob...