Musnad Ahmad 26:530

Hushaym narrated to us, Khalid informed us, from Ibn Sirin, that Anas ibn Malik witnessed the funeral of a man from the Ansar. He said: "They manifested seeking forgiveness (for him), and Anas did not disapprove of that." Hushaym said: Khalid said in his hadith: "And they entered him from the direction of the feet of the grave." Hushaym said once: A man from the Ansar died in Basra, and Anas ibn Malik witnessed it, "and they manifested seeking forgiveness for him."