كتاب الحج
15  
The Book of Pilgrimage
(46)
Chapter: The Talbiyah and the Takbir when going from Mina to 'Arafat on the day of 'Arafat
(46)
باب التَّلْبِيَةِ وَالتَّكْبِيرِ فِي الذِّهَابِ مِنْ مِنًى إِلَى عَرَفَاتٍ فِي يَوْمِ عَرَفَةَ ‏
Sahih Muslim 1285 a

Muhammad b. Abu Bakr al-Thaqafi asked Anas b. Malik (Allah be pleased with him), while on their way from Mina to 'Arafa in the morning:

What did you do on this day in the company of Allah's Messenger (ﷺ)? Thereupon he said: One of us pronounced Tahlil, and he met with no disapproval, and one of us pronounced Takbir, and he also met with no disapproval.
وَحَدَّثَنَا يَحْيَى بْنُ يَحْيَى، قَالَ قَرَأْتُ عَلَى مَالِكٍ عَنْ مُحَمَّدِ بْنِ أَبِي بَكْرٍ الثَّقَفِيِّ، أَنَّهُ سَأَلَ أَنَسَ بْنَ مَالِكٍ وَهُمَا غَادِيَانِ مِنْ مِنًى إِلَى عَرَفَةَ كَيْفَ كُنْتُمْ تَصْنَعُونَ فِي هَذَا الْيَوْمِ مَعَ رَسُولِ اللَّهِ صلى الله عليه وسلم فَقَالَ كَانَ يُهِلُّ الْمُهِلُّ مِنَّا فَلاَ يُنْكَرُ عَلَيْهِ وَيُكَبِّرُ الْمُكَبِّرُ مِنَّا فَلاَ يُنْكَرُ عَلَيْهِ ‏.‏
Reference : Sahih Muslim 1285a
In-book reference : Book 15, Hadith 302
USC-MSA web (English) reference : Book 7, Hadith 2939
  (deprecated numbering scheme)