Musnad Abu Ya'la al-Mawsili 109:189

Masruq ibn al-Marzuban narrated to us, Hafs narrated to us, from Ja'far, from his father, from Jabir: That the Prophet (peace and blessings of Allah be upon him) combined the Dhuhr and 'Asr prayers at 'Arafat with one Adhan and two Iqamahs. And [he combined] the Maghrib and 'Isha prayers with one Adhan and two Iqamahs.