كتاب الحدود
10  
Hudud
Muslim transmitted on the authority of 'Ali (RAA) concerning the story of al-Walid bin 'Uqbah that the Messenger of Allah inflicted forty lashes, Abu Bakr (RAA) forty lashes and 'Umar (RAA) eighty. All of them are in accordance with the Sunnah of the Prophet (ﷺ) but this one (the eighty lashes) is preferable to me.
وَلِمُسْلِمٍ: عَنْ عَلِيٍّ ‏- رضى الله عنه ‏- ‏-فِي قِصَّةِ اَلْوَلِيدِ بْنِ عَقَبَةَ‏- { جَلَدَ اَلنَّبِيُّ ‏- صلى الله عليه وسلم ‏-أَرْبَعِينَ, وَأَبُو بَكْرٍ أَرْبَعِينَ, وَعُمَرُ ثَمَانِينَ, وَكُلٌّ سُنَّةٌ, وَهَذَا أَحَبُّ }

Sunnah.com reference : Book 10, Hadith 39
English translation : Book 10, Hadith 1281
Arabic reference : Book 10, Hadith 1242