Musnad Abu Ya'la al-Mawsili 45:2

Abu Bakr narrated to us, Mu'adh ibn Mu'adh and 'Abd al-A'la narrated to us, they said: Sa'id ibn Abi 'Arubah narrated to us, from Qatadah, from Anas ibn Malik, from Abu Talhah, who said: When the Prophet, peace and blessings of Allah be upon him, would overcome a people, he liked to stay in their territory for three [days].