Jami` at-Tirmidhi 245
جامع الترمذي#245Da'ifIbn Abbas narrated:"The Prophet would open his Salat with (Bismillahir-Rahmanir-Rahim)
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Ahmad Muhammad ShakirDaif Isnaad
Al-AlbaniDaif Isnaad
Zubair Ali ZaiDaif
In-book reference: 2:97