Abu Dawud
Jihad
Book Number: 008 / Hadith Number: 2776
Narated By Abdullah ibn Umar : When the Apostle of Allah (pbuh) arrived from his hajj, he entered Medina, and made (his camel) kneel down at the gate of his mosque; and he entered it and offered two rak'ahs of prayer; he then returned to his home. Nafi' said: Ibn Umar also used to do so.