Musnad Ahmad 33:978

Yazid narrated to us, Hajjaj ibn Artah informed us, from Abu al-Zubayr, from Jabir ibn Abdullah, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "Whoever has a sharecropping agreement between him and his brother, and he wishes to sell it, let him offer it to his partner, for he is more entitled to it for the price."