Sunan an-Nasa'i 649
سنن النسائي#649SahihIt was narrated from Al-Aswad that Bilal said:"The final words of the Adhan are: 'Allahu Akbar, Allahu Akbar; La ilaha illallah (Allah is the Greatest, Allah is the Greatest, there is none worthy of worship except Allah)
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Abu GhuddahSahih Isnaad
Al-AlbaniSahih Isnaad
Zubair Ali ZaiHasan
In-book reference: 7:24