مُسْنَدُ أَحْمَدَ
Musnad Ahmad 2213
Musnad of 'Abdullah bin al-'Abbas bin 'Abdul-Muttalib from the Prophet
It was narrated that Ibn 'Abbas (رضي الله عنه) said: The Messenger of Allah (ﷺ) trotted for three circuits of the House, and when he reached the Yemeni Corner, he began to walk, until he reached the [Black Stone, then he trotted, and he walked for four circuits. And Ibn 'Abbas (رضي الله عنه) said: And that was Sunnah.
Musnad Ahmad 2220Sahech]