Salim bin Abdullah (may Allah have mercy on him) narrates from his father, Sayyiduna Abdullah bin Umar (may Allah be pleased with them both), that the Messenger of Allah (peace and blessings be upon him) led the Maghrib and Isha prayers together at Muzdalifah. Ibn Abi Dhi'b (may Allah have mercy on him) said: No call was made for either of them except the iqamah, and he offered no voluntary prayer between them, nor after them.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 1914