Musnad Ahmad 298:11

'Abd al-Razzaq narrated to us, he said: Ma'mar narrated to us, from Ayyub, from Humayd ibn Hilal, he said: Hisham ibn 'Amir informed us, he said: My father was killed on the day of Uhud. The Prophet, peace and blessings of Allah be upon him, said: "Dig, widen, make it good, and bury two or three in the grave, and put forward the one among them who knew the most Quran." My father was the third of three, and he was the one who knew the most Quran among them, so he was put forward.