Language:
كتاب فرض الخمس
57  
One-fifth of Booty to the Cause of Allah (Khumus)
(9)
Chapter: The war booty is for those who witness the battles
(9)
باب الْغَنِيمَةُ لِمَنْ شَهِدَ الْوَقْعَةَ
Sahih al-Bukhari 3125

Narrated Aslam:

`Umar said, "Were it not for those Muslims who have not come to existence yet, I would have distributed (the land of) every town I conquer among the fighters as the Prophet (ﷺ) distributed the land of Khaibar."

حَدَّثَنَا صَدَقَةُ، أَخْبَرَنَا عَبْدُ الرَّحْمَنِ، عَنْ مَالِكٍ، عَنْ زَيْدِ بْنِ أَسْلَمَ، عَنْ أَبِيهِ، قَالَ قَالَ عُمَرُ ـ رضى الله عنه لَوْلاَ آخِرُ الْمُسْلِمِينَ مَا فَتَحْتُ قَرْيَةً إِلاَّ قَسَمْتُهَا بَيْنَ أَهْلِهَا كَمَا قَسَمَ النَّبِيُّ صلى الله عليه وسلم خَيْبَرَ‏.‏
Reference : Sahih al-Bukhari 3125
In-book reference : Book 57, Hadith 34
USC-MSA web (English) reference : Vol. 4, Book 53, Hadith 354
  (deprecated numbering scheme)