Musannaf Ibn Abi Shayba 13:1296

Abu Bakr narrated to us, he said: Umar ibn Ayyub narrated to us, from Ja'far ibn Burqan, from Thabit ibn al-Hajjaj, from Zayd ibn Thabit, who said: The Messenger of Allah (may Allah bless him and grant him peace) forbade *al-mukhabarah*. I said: "And what is *al-mukhabarah*?" He said: "That you take the land for a half, or a third, or a quarter."