Musnad Ahmad 4:16

Abdullah narrated to us, Ubaydullah ibn Umar al-Qawariri narrated to me, al-Qasim ibn al-Hakam ibn Aws al-Ansari narrated to me, Abu Ubadah al-Zuraqi al-Ansari—from the people of Medina—narrated to me, from Zayd ibn Aslam, from his father, who said: I witnessed Uthman on the day he was besieged at the place of the funerals, and if a stone had been thrown, it would not have landed except on a man’s head. I saw Uthman looking out from the small door (khawkha) that is adjacent to the Station of Gabriel, peace be upon him. He said: "O people, is Talha among you?" They remained silent. Then he said: "O people, is Talha among you?" They remained silent. Then he said: "O people, is Talha among you?" They remained silent. Then he said: "O people, is Talha among you?" Talha ibn Ubaydullah stood up, and Uthman said to him: "Do I not see you here? I did not think that you would be among a group that hears my call three times and then does not answer me. I adjure you by Allah, O Talha, do you remember the day you and I were with the Messenger of Allah, may Allah bless him and grant him peace, in such-and-such a place, and there was no one with him from his companions except me and you?" He said: "Yes." Uthman said: "The Messenger of Allah, may Allah bless him and grant him peace, said to you: 'O Talha, there is no prophet except that he has a companion from his nation with him in Paradise, and this Uthman ibn Affan—meaning me—is my companion with me in Paradise.'" Talha said: "O Allah, yes." Then he departed.