Sahih Bukhari Volume 003, Book 039, Hadith Number 537.
Narated By Hanzla bin Qais : Rafi bin Khadij said, "My two uncles told me that they (i.e. the companions of the Prophet) used to rent the land in the life-time of the Prophet for the yield on the banks of water streams (rivers) or for a portion of the yield stipulated by the owner of the land. The Prophet forbade it." I said to Rafi, "What about renting the land for Dinars and Dirhams?" He replied, "There is no harm in renting for Dinars-Dirhams. Al-Laith said, "If those who have discernment for distinguishing what is legal from what is illegal looked into what has been forbidden concerning this matter they would not permit it, for it is surrounded with dangers."