مسند أحمد

It was narrated from Ibn `Abbas (رضي الله عنه) that he said: Some men of good character, among whom was ‘Umar, who is the best of them in my view, testified in my presence that the Messenger of Allah (ﷺ) forbade praying after Fajr prayer until the sun rose, and after Asr prayer until it (the sun) set.