Language:
كتاب المحصر
27  
Pilgrims Prevented from Completing the Pilgrimage
(3)
Chapter: The slaughtering before shaving the head (in case) one is prevented
(3)
باب النَّحْرِ قَبْلَ الْحَلْقِ فِي الْحَصْرِ
Sahih al-Bukhari 1811

Narrated Al-Miswar:

Allah's Messenger (ﷺ) slaughtered (the Hadi) before he had his head shaved and then he ordered his Companions to do the same.

حَدَّثَنَا مَحْمُودٌ، حَدَّثَنَا عَبْدُ الرَّزَّاقِ، أَخْبَرَنَا مَعْمَرٌ، عَنِ الزُّهْرِيِّ، عَنْ عُرْوَةَ، عَنِ الْمِسْوَرِ ـ رضى الله عنه ـ أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم نَحَرَ قَبْلَ أَنْ يَحْلِقَ، وَأَمَرَ أَصْحَابَهُ بِذَلِكَ‏.‏
Reference : Sahih al-Bukhari 1811
In-book reference : Book 27, Hadith 6
USC-MSA web (English) reference : Vol. 3, Book 28, Hadith 38
  (deprecated numbering scheme)