Musnad Abu Ya'la al-Mawsili 216:3

Abu Khaythama narrated to us, Sufyan ibn 'Uyayna narrated to us, from 'Amr ibn Dinar, from Jabir ibn Zayd, from Ibn 'Abbas, that Maymuna informed him that she used to perform ghusl (ritual bath), she and the Messenger of Allah, may Allah bless him and grant him peace, from a single vessel.