مُسْنَدُ أَحْمَدَ
Musnad Ahmad 3928
Musnad of Abdullah bin Mas'ood
It was narrated that 'Abdullah bin Mas'ood (رضي الله عنه) said: I prayed two rak'ahs with the Messenger of Allah (ﷺ) in Mina, and two rak'ahs with Abu Bakr (رضي الله عنه), and two rak'wits with 'Umar (رضي الله عنه), and I wish that I had of these four rak'ahs two that are accepted.
Musnad Ahmad 3953Its isnad is saheeh, al-Bukhari (1084) and Muslim (695)