Musnad Abu Ya'la al-Mawsili 127:3

Al-Azraq ibn Ali Abu al-Jahm narrated to us, Hassan narrated to us, Yusuf narrated to us, from Abu Ishaq, from Burayd ibn Abi Maryam, from Anas ibn Malik, who said: The Messenger of Allah (may Allah bless him and grant him peace) said: "Whoever mentions me, let him send blessings upon me. And whoever sends one blessing upon me, Allah sends ten blessings upon him."