Sunan Abi Dawud 1002
سنن أبي داود#1002SahihIbn ‘Abbas said:The end of the prayer of the Messenger of Allah (ﷺ) was known by the takbir (pronounced aloud)
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
Zubair Ali ZaiSahih Bukhari (482) Sahih Muslim (583)
In-book reference: 2:613