حَدَّثَنَا يَعْقُوبُ بْنُ إِبْرَاهِيمَ، حَدَّثَنَا هُشَيْمٌ، أَخْبَرَنَا أَبُو بِشْرٍ، عَنْ سَعِيدِ بْنِ جُبَيْرٍ، عَنِ ابْنِ عَبَّاسٍ ـ رضى الله عنهما ـ جَمَعْتُ الْمُحْكَمَ فِي عَهْدِ رَسُولِ اللَّهِ صلى الله عليه وسلم فَقُلْتُ لَهُ وَمَا الْمُحْكَمُ قَالَ الْمُفَصَّلُ‏.‏

Narrated Sa`id bin Jubair: Ibn `Abbas said, "I have learnt all the Muhkam Suras during the life time of Allah's Messenger (PBUH)." I said to him, 'What is meant by the Muhkam?" He replied, "The Mufassal." Translation Not Available

Book Ref: Sahih Bukhari Book 66 Hadith 5036
Web Ref:  Sahih Bukhari Vol 6 Book 61 Hadith 555