The Book of Pilgrimage (Kitab Al-Hajj)

Muslim :: Book 7 : Hadith 2951

Ibn Umar (Allah be pleased with them) reported that Allah's Messenger (may peace be upon him) observed the sunset and 'Isha' prayers together at Muzdalifa.

Source materials are from the University of Southern California MSA site
Hadith eBooks converted from Imaan Star