كتاب الوصية
25  
The Book of Wills
(1)
Chapter: Bequeathing One-Third
(1)
باب الْوَصِيَّةِ بِالثُّلُثِ ‏‏
Sahih Muslim 1628 e

This hadith has been narrated on the authority of Simak with the same chain of transmitters. But he did not mention:

" It was then that one-third became permissible."
وَحَدَّثَنِي مُحَمَّدُ بْنُ الْمُثَنَّى، وَابْنُ، بَشَّارٍ قَالاَ حَدَّثَنَا مُحَمَّدُ بْنُ جَعْفَرٍ، حَدَّثَنَا شُعْبَةُ، عَنْ سِمَاكٍ، بِهَذَا الإِسْنَادِ نَحْوَهُ ‏.‏ وَلَمْ يَذْكُرْ فَكَانَ بَعْدُ الثُّلُثُ جَائِزًا ‏.‏
Reference : Sahih Muslim 1628e
In-book reference : Book 25, Hadith 10
USC-MSA web (English) reference : Book 13, Hadith 3995
  (deprecated numbering scheme)