(47) باب الإِفَاضَةِ مِنْ عَرَفَاتٍ إِلَى الْمُزْدَلِفَةِ وَاسْتِحْبَابِ صَلاَتَىِ الْمَغْرِبِ وَالْعِشَاءِ جَمْعًا بِالْمُزْدَلِفَةِ فِي هَذِهِ اللَّيْلَةِ
Ibn Umar (Allah be pleased with them) reported that Allah's Messenger (ﷺ) observed the sunset and 'Isha' prayers together at Muzdalifa.
Reference: Sahih Muslim 703 e
In-book reference: Book 15, Hadith 314
USC-MSA web (English) reference(deprecated numbering scheme): Book 7, Hadith 2951