حَدَّثَنَا عَلِيُّ بْنُ مُحَمَّدٍ، حَدَّثَنَا وَكِيعٌ، عَنْ هِشَامِ بْنِ عُرْوَةَ، عَنْ أَبِيهِ، عَنِ ابْنِ عَبَّاسٍ، قَالَ وَدِدْتُ أَنَّ النَّاسَ، غَضُّوا مِنَ الثُّلُثِ إِلَى الرُّبُعِ لأَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ ‏"‏ الثُّلُثُ كَبِيرٌ - أَوْ كَثِيرٌ - ‏"‏ ‏.‏

It was narrated that Ibn Abbas said: “I would like the people to reduce (the will) from one third to one quarter, because the Messenger of Allah (PBUH) said: 'One third is a lot.'” Translation Not Available

Book Ref: Sunan Ibn Majah Book 22 Hadith 2711
Web Ref:  Sunan Ibn Majah Vol 3 Book 22 Hadith 2711