Sayyiduna Ibn Abbas (may Allah be pleased with them both) said: "The Messenger of Allah (peace and blessings be upon him) passed away when I had already recited the Muhkam of the Qur'an." Shu'bah said: I asked Abu Bishr: What is the Muhkam? He said: The Mufassal.
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 10531