Musnad Ahmad 26:450

Muhammad ibn Bakr narrated to us, Sa'id informed us, from Qatadah, from al-Hasan and al-'Ala' ibn Ziyad, from 'Imran ibn Husayn, from 'Abdullah ibn Mas'ud, who said: We were conversing in the presence of the Messenger of Allah, peace and blessings of Allah be upon him, one night, until we prolonged the conversation, and he mentioned it.