Narrated 'Abdul 'Aziz bin Rufai':

Shaddad bin Ma'qil and I entered upon Ibn 'Abbas. Shaddad bin Ma'qil asked him, "Did the Prophet leave anything (besides the Qur'an)?" He replied. "He did not leave anything except what is Between the two bindings (of the Qur'an)." Then we visited Muhammad bin Al-Hanafiyya and asked him (the same question). He replied, "The Prophet did not leave except what is between the bindings (of the Qur'an)."

حَدَّثَنَا قُتَيْبَةُ بْنُ سَعِيدٍ، حَدَّثَنَا سُفْيَانُ، عَنْ عَبْدِ الْعَزِيزِ بْنِ رُفَيْعٍ، قَالَ دَخَلْتُ أَنَا وَشَدَّادُ بْنُ مَعْقِلٍ، عَلَى ابْنِ عَبَّاسٍ رضى الله عنهما فَقَالَ لَهُ شَدَّادُ بْنُ مَعْقِلٍ أَتَرَكَ النَّبِيُّ ﷺ مِنْ شَىْءٍ قَالَ مَا تَرَكَ إِلاَّ مَا بَيْنَ الدَّفَّتَيْنِ. قَالَ وَدَخَلْنَا عَلَى مُحَمَّدِ ابْنِ الْحَنَفِيَّةِ فَسَأَلْنَاهُ فَقَالَ مَا تَرَكَ إِلاَّ مَا بَيْنَ الدَّفَّتَيْنِ.