Musnad Ahmad 2:130

Abu al-Nadr narrated to us, Abu Aqil narrated to us, Mujalid ibn Sa'id narrated to us, Amir informed us, from Masruq ibn al-Ajda', who said: I met Umar ibn al-Khattab, and he said to me: "Who are you?" I said: "Masruq ibn al-Ajda'." Umar said: "I heard the Messenger of Allah, may Allah bless him and grant him peace, say: 'Al-Ajda' is a devil.' Rather, you are Masruq ibn Abd al-Rahman." Amir said: I saw him in the register (diwan) written as: Masruq ibn Abd al-Rahman. I said: "What is this?" He replied: "This is what Umar, may Allah be pleased with him, named me."