Sunan Abi Dawud 820
سنن أبي داود#820Da'ifAbu hurairah said:The Messenger of Allah (ﷺ) commanded me to announce that prayer is not valid but with the recitation of Fatihat al-kitab and something more
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Al-AlbaniSahih
Muhammad Muhyi Al-Din Abdul HamidSahih
Shuaib Al ArnautSahih Lighairihi
Zubair Ali ZaiDaif
In-book reference: 2:430