Prophetic Commentary on the Qur'an (Tafseer of the Prophet
(pbuh)) 
Bukhari :: Book 6 :: Volume 60 :: Hadith 67
Narrated Ibn Abbas:
The last Verse (in the Quran) revealed to the Prophet was the Verse dealing with usury (i.e. Riba).
Prophetic Commentary on the Qur'an (Tafseer of the Prophet (pbuh))
Bukhari :: Book 6 :: Volume 60 :: Hadith 67
Narrated Ibn Abbas:
The last Verse (in the Quran) revealed to the Prophet was the Verse dealing with usury (i.e. Riba).