Musnad Ahmad 1153:824

Mu'awiyah ibn 'Amr narrated to us, he said: Za'idah narrated to us, he said: 'Ata' ibn al-Sa'ib al-Thaqafi narrated to us, from Abu Salamah ibn 'Abd al-Rahman ibn 'Awf, he said: 'Aishah narrated to me: "That the Messenger of Allah, peace and blessings of Allah be upon him, when he performed ghusl (ritual bath) from janabah (major ritual impurity), he would rinse his mouth and snuff water into his nose."