Language:
كتاب النكاح
67  
Wedlock, Marriage (Nikaah)
(69)
Chapter: Al-Walima is to be given even with one sheep
(68)
باب الْوَلِيمَةِ وَلَوْ بِشَاةٍ
Sahih al-Bukhari 5169

Narrated Anas:

Allah's Messenger (ﷺ) manumitted Safiyya and then married her, and her Mahr was her manumission, and he gave a wedding banquet with Hais (a sort of sweet dish made from butter, cheese and dates).

حَدَّثَنَا مُسَدَّدٌ، عَنْ عَبْدِ الْوَارِثِ، عَنْ شُعَيْبٍ، عَنْ أَنَسٍ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم أَعْتَقَ صَفِيَّةَ، وَتَزَوَّجَهَا وَجَعَلَ عِتْقَهَا صَدَاقَهَا، وَأَوْلَمَ عَلَيْهَا بِحَيْسٍ‏.‏
Reference : Sahih al-Bukhari 5169
In-book reference : Book 67, Hadith 104
USC-MSA web (English) reference : Vol. 7, Book 62, Hadith 98
  (deprecated numbering scheme)