Book of Jasher 84:14
And in the thirty-sixth year of the children of Israel's departing from Egypt the Lord smote the heart of Sihon, king of the Amorites, and he waged war, and went forth to fight against the children of Moab.
And in the thirty-sixth year of the children of Israel's departing from Egypt the Lord smote the heart of Sihon, king of the Amorites, and he waged war, and went forth to fight against the children of Moab.