The Book on Government
33/10. Chapter:
The obligation of fulfilling oaths of allegiance is owed to the first of two Caliphs
Sahih Muslim
وَحَدَّثَنَا أَبُو بَكْرِ بْنُ أَبِي شَيْبَةَ، وَابْنُ، نُمَيْرٍ وَأَبُو سَعِيدٍ الأَشَجُّ قَالُوا حَدَّثَنَا وَكِيعٌ، ح وَحَدَّثَنَا أَبُو كُرَيْبٍ، حَدَّثَنَا أَبُو مُعَاوِيَةَ، كِلاَهُمَا عَنِ الأَعْمَشِ، بِهَذَا الإِسْنَادِ نَحْوَهُ .
This hadith has been narrated on the authority of A'mash with a different chain of transmitters.
Reference : Sahih Muslim 1844bIn-book reference : Book 33, Hadith 75USC-MSA web (English) reference : Book 20, Hadith 4547