Musnad Ahmad 30:3313

Ibn Numayr narrated to us, Isma'il ibn Abi Khalid narrated to us, from his father, who said: Abu Hurayrah used to pray in Medina in a manner similar to the prayer of Qays ibn Abi Hazim. I said to him: "O Abu Hurayrah, is this how the Messenger of Allah, may Allah bless him and grant him peace, used to pray?" He said: "And what do you disapprove of in my prayer?" I said: "No, by Allah, nothing but good; I only wanted to ask you." He said: "Yes, and I am more proficient."