Musnad Abu Ya'la al-Mawsili 117:101

Shayban ibn Farrukh narrated to us, Hammad narrated to us, Thabit al-Bunani narrated to us, from Anas, that the Messenger of Allah (may Allah bless him and grant him peace) said: "I was brought the Buraq, and it is a white beast, long, taller than a donkey and shorter than a mule. It places its hoof at the furthest extent of its gaze." He said: "So I rode it until I came to Bayt al-Maqdis (Jerusalem)." He said: "Then I tethered it to the ring to which the prophets tethered [their mounts]. Then I entered the mosque and prayed two rak'ahs in it, then I went out."