Sahih Bukhari Volume 008, Book 075, Hadith Number 328.

Narated By Ibn 'Abbas : One night I slept at the house of Maimuna. The Prophet woke up, answered the call of nature, washed his face and hands, and then slept. He got up (late at night), went to a water skin, opened the mouth thereof and performed ablution not using much water, yet he washed all the parts properly and then offered the prayer. I got up and straightened my back in order that the Prophet might not feel that I was watching him, and then I performed the ablution, and when he got up to offer the prayer, stood on his left. He caught hold of my ear and brought me over to his right side. He offered thirteen Rak'at in all and then lay down and slept till he started blowing out his breath as he used to do when he slept. In the meantime Bilal informed the Prophet of the approaching time for the (Fajr) prayer, and the Prophet offered the Fajr (Morning) prayer without performing new ablution. He used to say in his invocation, Allaihumma ij'al fi qalbi nuran wa fi basari nuran, wa fi sam'i nuran, wa'an yamini nuran, wa'an yasari nuran, wa fawqi nuran, wa tahti nuran, wa amami nuran, wa khalfi nuran, waj'al li nuran." Kuraib (a sub narrator) said, "I have forgotten seven other words, (which the Prophet mentioned in this invocation). I met a man from the offspring of Al-'Abbas and he narrated those seven things to me, mentioning, '(Let there be light in) my nerves, my flesh, my blood, my hair and my body,' and he also mentioned two other things."