Musnad Ahmad 27:986

Bahz narrated to us, Shu'bah narrated to us, Jabalah narrated to us, he said: We were in Medina with the expedition of the people of Iraq, and a year of drought afflicted us. Abdullah ibn al-Zubayr began to provide us with dates. Abdullah ibn Umar would pass by us and say: "Do not practice *al-qiran* (combining two dates together when eating), for the Messenger of Allah, peace and blessings of Allah be upon him, forbade *al-qiran*, unless a man asks his brother for permission."