Ibn Shihab said: Among those of the Ansar, and then of Banu al-Najjar, who were present at al-Aqabah, is this name: Abu Umamah Sayyiduna As'ad bin Zurarah (may Allah be pleased with him), and he was a leader (naqib).
Hadith Referenceالمعجم الكبير للطبراني / باب الألف / 893