Musnad Abu Ya'la al-Mawsili 117:130

Qatan ibn Nusayr narrated to us, Ja'far ibn Sulayman narrated to us, Thabit narrated to us, from Anas, who said: The Messenger of Allah (may Allah bless him and grant him peace) established brotherhood between his companions. He established brotherhood between Salman and Abu al-Darda’. And he established brotherhood between 'Awf ibn Malik and Sa'b ibn Juththamah.