Musannaf Ibn Abi Shayba 1:866

Waki' narrated to us, he said: Mis'ar narrated to me, from Abu Bakr bin 'Umarah bin Ruwaybah, from a woman, from Umm Salamah, who said: "If one of us were to perform ghusl (ritual bath) from janabah (major ritual impurity), she would undo her braids."