Musannaf Ibn Abi Shayba 24:159

Waki’ narrated to us, he said: Al-A’mash narrated to us, from Malik ibn al-Harith, from Abu Khalid, who said: I arrived as a delegate to Umar, and he favored the people of Ash-Sham over us in the stipend. We said to him [something], so he said: "O people of Kufa, are you distressed that I favored the people of Ash-Sham over you in the stipend due to the distance of their journey? For I have indeed preferred you with the son of Umm ‘Abd."