Musannaf Ibn Abi Shayba 3:2191

Abu Mu'awiyah narrated to us, from Ibn Abi Dhi'b, from Abu Jabir al-Bayadi, from Sa'id ibn al-Musayyib, that the Prophet (peace and blessings of Allah be upon him) led the people in prayer while he was in a state of major ritual impurity (junub), so he repeated [the prayer] and they repeated [the prayer].