مُسْنَدُ أَحْمَدَ
Musnad Ahmad 2524
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) was treated with cupping when he was fasting.
Musnad Ahmad 2536Its isnad is saheeh]