Musnad Ahmad 307:10

Mu'adh ibn Mu'adh narrated to us, he said: Sa'id ibn Abi 'Arubah narrated to us, from Qatadah, from Anas ibn Malik, from Abu Talhah: "That the Messenger of Allah, peace and blessings of Allah be upon him, when he overcame a people, he liked to stay in their territory for three [days]."