Jami` at-Tirmidhi 277
جامع الترمذي#277HasanAmir bin Sa'd [bin Abi Waqqas] narrated from his father:"The Prophet ordered placing the hands (on the ground) keeping the feet erect. (by resting feet on the toes and making the tips of the toes facing the Qiblah)
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Ahmad Muhammad ShakirHasan
Al-AlbaniHasan
In-book reference: 2:129