ENOfficial
He said that God's Messenger did not hold such a wedding-feast for any of his wives as he did for Zainab. He held a wedding-feast with a sheep. (Bukhari and Muslim.)
Source: sunnah.com
Other translations
Arabic
وَعَنْهُ قَالَ: مَا أَوْلَمَ رَسُولِ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ عَلَى أَحَدٍ مِنْ نِسَائِهِ مَا أولم على زَيْنَب أولم بِشَاة
sunnah.com