كتاب النكاح
16  
The Book of Marriage
(3)
Chapter: Mut'ah Marriage: It was permitted then abrograted, then permitted then abrogated, and it will remain Forbidden until the day of resurrection
(3)
باب نِكَاحِ الْمُتْعَةِ وَبَيَانِ أَنَّهُ أُبِيحَ ثُمَّ نُسِخَ ثُمَّ أُبِيحَ ثُمَّ نُسِخَ وَاسْتَقَرَّ تَحْرِيمُهُ إِلَى يَوْمِ الْقِيَامَةِ
Sahih Muslim 1404 c

This hadith has been narrated on the authority of Isma'il with the same chain of transmitters (and the words are):

" We were young, so we said: Allah's Messenger, should we not have ourselves castrated? But he (the narrator) did not say; We were on an expedition."
وَحَدَّثَنَا أَبُو بَكْرِ بْنُ أَبِي شَيْبَةَ، حَدَّثَنَا وَكِيعٌ، عَنْ إِسْمَاعِيلَ، بِهَذَا الإِسْنَادِ قَالَ كُنَّا وَنَحْنُ شَبَابٌ فَقُلْنَا يَا رَسُولَ اللَّهِ أَلاَ نَسْتَخْصِي وَلَمْ يَقُلْ نَغْزُو ‏.‏
Reference : Sahih Muslim 1404c
In-book reference : Book 16, Hadith 15
USC-MSA web (English) reference : Book 8, Hadith 3245
  (deprecated numbering scheme)