The prayer and the supplication of the Prophet (saws) at night Sahih Muslim 763 c
Translation
Makhrama b. Sulaiman narrated it with the same chain of narrators and he made this addition
"He then went to the water-skin and brushed his teeth and performed ablution well. He did not pour water but a little. He then awakened me and I stood up," and the rest of the hadith is the same.