Musnad Ahmad 937:215

'Affan narrated to us, Abu 'Awanah narrated to us, from Abu Bishr, from Talq ibn Habib, from Bashir ibn Ka'b al-'Adawi, from Abu Dharr, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "Do you have an interest in a treasure from the treasures of Paradise?" He said: I said: "Yes." He said: "La hawla wa la quwwata illa billah (There is no power and no strength except by Allah)."