Musannaf Ibn Abi Shayba 1:740

Hussain bin Ali narrated to us, from Za'idah, who said: 'Ata' bin al-Sa'ib narrated to us, he said: Abu Salamah bin Abd al-Rahman narrated to me, he said: Aisha narrated to me, that the Messenger of Allah (may Allah bless him and grant him peace), when he performed ghusl (ritual bath) from janabah (major ritual impurity), would rinse his mouth and sniff water into his nose three times.