Sahih Bukhari | Volume 9 | Hadith Number 310

Narrated by 'Abdullah bin Dinar
I witnessed Ibn 'Umar when the people gathered around 'Abdul Malik. Ibn 'Umar wrote: I gave 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 as much as I can; and my sons too, give the same pledge.'