Musnad Abu Ya'la al-Mawsili 150:173

Abu Ma'mar narrated to us, Sufyan narrated to us, from al-Zuhri, from Urwah, who said: Abu Hurayrah sat by the chamber of Aisha while she was praying, and he was speaking, saying: "Do you not hear, O lady of the chamber?" When she finished her prayer, she said: "O Urwah, do you not hear this and his speech? Indeed, the Messenger of Allah (peace and blessings of Allah be upon him) used to speak in a manner that if a counter were to count it, he would have enumerated it."