Language:
كتاب الفرائض
85  
Laws of Inheritance (Al-Faraa'id)
(10)
Chapter: The inheritance of husband along with the offspring and other relatives
(10)
باب مِيرَاثِ الزَّوْجِ مَعَ الْوَلَدِ وَغَيْرِهِ
Sahih al-Bukhari 6739

Narrated Ibn `Abbas:

(During the early days of Islam), the inheritance used to be given to one's offspring and legacy used to be bequeathed to the parents, then Allah cancelled what He wished from that order and decreed that the male should be given the equivalent of the portion of two females, and for the parents one-sixth for each of them, and for one's wife one-eighth (if the deceased has children) and one-fourth (if he has no children), for one's husband one-half (if the deceased has no children) and one-fourth (if she has children).

حَدَّثَنَا مُحَمَّدُ بْنُ يُوسُفَ، عَنْ وَرْقَاءَ، عَنِ ابْنِ أَبِي نَجِيحٍ، عَنْ عَطَاءٍ، عَنِ ابْنِ عَبَّاسٍ ـ رضى الله عنهما ـ قَالَ كَانَ الْمَالُ لِلْوَلَدِ، وَكَانَتِ الْوَصِيَّةُ لِلْوَالِدَيْنِ، فَنَسَخَ اللَّهُ مِنْ ذَلِكَ مَا أَحَبَّ، فَجَعَلَ لِلذَّكَرِ مِثْلَ حَظِّ الأُنْثَيَيْنِ، وَجَعَلَ لِلأَبَوَيْنِ لِكُلِّ وَاحِدٍ مِنْهُمَا السُّدُسُ، وَجَعَلَ لِلْمَرْأَةِ الثُّمُنَ وَالرُّبُعَ، وَلِلزَّوْجِ الشَّطْرَ وَالرُّبُعَ‏.‏
Reference : Sahih al-Bukhari 6739
In-book reference : Book 85, Hadith 16
USC-MSA web (English) reference : Vol. 8, Book 80, Hadith 731
  (deprecated numbering scheme)