Musnad Abu Ya'la al-Mawsili 149:62

Ishaq ibn Abi Isra'il narrated to us, Sufyan narrated to us, from al-Zuhri, from Urwah, from Aisha, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "No one's wealth has benefited us as much as the wealth of Abu Bakr has benefited us."