The Book of Pilgrimage
15/47. Chapter:
Departing from 'Arafat to Al-Muzdalifah. It is recommended to pray Maghrib and 'Isha together in Al-Muzdalifah on this night
Sahih Muslim
وَحَدَّثَنِيهِ زُهَيْرُ بْنُ حَرْبٍ، حَدَّثَنَا وَكِيعٌ، حَدَّثَنَا شُعْبَةُ، بِهَذَا الإِسْنَادِ وَقَالَ صَلاَّهُمَا بِإِقَامَةٍ وَاحِدَةٍ .
Shu'ba reported this hadith with the same chain of transmitters and said: He (the Holy Prophet) observed the two prayers (together) with one iqama.
Reference : Sahih Muslim 1288cIn-book reference : Book 15, Hadith 317USC-MSA web (English) reference : Book 7, Hadith 2953