Musannaf Ibn Abi Shayba 27:885

Al-Fadl ibn Dukayn narrated to us, from Abdullah ibn Amir, from Imran ibn Abi Anas, from Sahl ibn Sa’d, from Ubayy ibn Ka’b, from the Prophet, may Allah bless him and grant him peace, who said: "The mosque which was founded upon righteousness is my mosque."