Sunan an-Nasa'i 3992
سنن النسائي#3992SahihIt was narrated that 'Abdullah said:"The Messenger of Allah [SAW] said: 'The first matter concerning which judgment will be passed among the people will be bloodshed
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Abu GhuddahSahih
Al-AlbaniSahih
Zubair Ali ZaiSahih - Agreed Upon
In-book reference: 37:27