كتاب الصلاة
2  
The Book of Prayer
Bulugh al-Maram 282
Narrated Abu Hurairah (RA):
Allah's Messenger (ﷺ) said: "Whenever you recite Surat Al-Fatiha, recite Bismillahir-Rahmanir-Rahim, for it is one of its Ayat (Verses)." [Reported by ad-Daraqutni who verified it as Mawquf - the saying of Abu Hurairah (RA)].
وَعَنْ أَبِي هُرَيْرَةَ ‏- رضى الله عنه ‏- قَالَ : قَالَ رَسُولُ اَللَّهِ ‏- صلى الله عليه وسلم ‏-{ إِذَا قَرَأْتُمْ اَلْفَاتِحَةِ فَاقْرَءُوا : ( بِسْمِ اَللَّهِ اَلرَّحْمَنِ اَلرَّحِيمِ )‏ , فَإِنَّهَا إِحْدَى آيَاتِهَا } رَوَاهُ اَلدَّارَقُطْنِيُّ , وَصَوَّبَ وَقْفَهُ .‏ 1
Reference : Bulugh al-Maram 282
In-book reference : Book 2, Hadith 282
English translation : Book 2, Hadith 280
Hadith Text
Reference