The Book of the Merits of the Companions
Sahih Muslim #6181
كتاب فضائل الصحابة رضى الله تعالى عنهم
حَدَّثَنَا عُبَيْدُ اللَّهِ بْنُ مُعَاذٍ، حَدَّثَنَا أَبِي، حَدَّثَنَا شُعْبَةُ، بِهَذَا الإِسْنَادِ وَزَادَ قَالَ شُعْبَةُ بَدَأَ بِهَذَيْنِ لاَ أَدْرِي بِأَيِّهِمَا بَدَأَ.
Ubaidullah b. Mu'adh reported it on the authority of his father Shu'ba with the same chain of transmitters and he made this addition. He made a mention of these two names but I do not know whose name he mentioned first.
حَدَّثَنَا عُبَيْدُ اللَّهِ بْنُ مُعَاذٍ، حَدَّثَنَا أَبِي، حَدَّثَنَا شُعْبَةُ، بِهَذَا الإِسْنَادِ وَزَادَ قَالَ شُعْبَةُ بَدَأَ بِهَذَيْنِ لاَ أَدْرِي بِأَيِّهِمَا بَدَأَ .
Ubaidullah b. Mu'adh reported it on the authority of his father Shu'ba with the same chain of transmitters and he made this addition. He made a mention of these two names but I do not know whose name he mentioned first.
— Sahih Muslim, Hadith 6181