كتاب الصلاة
2  
The Book of Prayer
Bulugh al-Maram 399
Both al-Bukhari and Muslim have also reported through Abu Hurairah (RA):
"Twenty-five degrees (more)."
وَلَهُمَا عَنْ أَبِي هُرَيْرَةَ: { بِخَمْسٍ وَعِشْرِينَ جُزْءًا } 1‏ .‏
Reference : Bulugh al-Maram 399
In-book reference : Book 2, Hadith 399
English translation : Book 2, Hadith 394
Hadith Text
Reference