Musannaf Ibn Abi Shayba 3:1192

Abu Dawud al-Tayalisi narrated to us, from Shu'bah, from Simak, from Jabir ibn Samurah, that the Prophet (peace be upon him) used to recite in the Dhuhr prayer: "Glorify the name of your Lord, the Most High." And in the morning (Fajr) prayer, he would recite something longer than that.