Urwah (may Allah have mercy on him), in listing the names of the Ansar who took part in Badr, said: Then from the Banu al-Harith bin al-Khazraj, of the Banu Imru' al-Qays bin Tha'labah bin Ka'b bin al-Khazraj bin al-Harith bin al-Khazraj: Abdullah bin Rawahah bin Imru' al-Qays (may Allah be pleased with him, also took part).
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 14009