Language:
كتاب الأحكام
93  
Judgments (Ahkaam)
(43)
Chapter: How do the people give the Bai'a to the Imam
(43)
باب كَيْفَ يُبَايِعُ الإِمَامُ النَّاسَ
Sahih al-Bukhari 7205

Narrated `Abdullah bin Dinar:

When the people took the oath of allegiance to `Abdul Malik, `Abdullah bin `Umar wrote to him: "To Allah's Slave, `Abdul Malik, Chief of the believers, I give the Pledge of allegiance that I will listen to and obey Allah's Slave, `Abdul Malik, Chief of the believers, according to Allah's Laws and the Traditions of His Apostle in whatever is within my ability; and my sons too, give the same pledge."

حَدَّثَنَا عَمْرُو بْنُ عَلِيٍّ، حَدَّثَنَا يَحْيَى، عَنْ سُفْيَانَ، قَالَ حَدَّثَنِي عَبْدُ اللَّهِ بْنُ دِينَارٍ، قَالَ لَمَّا بَايَعَ النَّاسُ عَبْدَ الْمَلِكِ كَتَبَ إِلَيْهِ عَبْدُ اللَّهِ بْنُ عُمَرَ إِلَى عَبْدِ اللَّهِ عَبْدِ الْمَلِكِ أَمِيرِ الْمُؤْمِنِينَ إِنِّي أُقِرُّ بِالسَّمْعِ وَالطَّاعَةِ لِعَبْدِ اللَّهِ عَبْدِ الْمَلِكِ أَمِيرِ الْمُؤْمِنِينَ، عَلَى سُنَّةِ اللَّهِ وَسُنَّةِ رَسُولِهِ، فِيمَا اسْتَطَعْتُ، وَإِنَّ بَنِيَّ قَدْ أَقَرُّوا بِذَلِكَ‏.‏
Reference : Sahih al-Bukhari 7205
In-book reference : Book 93, Hadith 65
USC-MSA web (English) reference : Vol. 9, Book 89, Hadith 312
  (deprecated numbering scheme)