Musnad Ahmad 33:997

Rawh narrated to us, Ibn Jurayj narrated to us, Abu al-Zubayr informed me that he heard Jabir ibn Abdullah saying: I heard the Messenger of Allah, peace and blessings of Allah be upon him, saying: "I hope that those who follow me from my nation on the Day of Resurrection will be a quarter of the people of Paradise." He said: So we said 'Allahu Akbar' (God is the Greatest). He said: "I hope that they will be a third of the people of Paradise." He said: So we said 'Allahu Akbar'. He said: "I hope that they will be half."