Sahih Muslim
The Book of Pilgrimage (Kitab Al-Hajj)
Book Number: 007 / Hadith Number: 2963
Ibn Shawwal (the freed slave of Umm Habiba) reported that he went to Umm Habiba (the wife of Allah's Apostle) who informed him that Allah's Apostle (may peace be upon him) sent her from Muzdalifa during the night.