Sunan an-Nasa'i 4139
سنن النسائي#4139SahihIt was narrated from 'Amr bin Shu'aib, from his father, from his grandfather, that:the Messenger of Allah went to a camel, and took a hair from its hump between his fingers and said: "I am not entitled to take anything from the Fay, not even this, except the Khumus, and the Khumus will come back to you
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Abu GhuddahHasan Sahih
Al-AlbaniHasan Sahih
Zubair Ali ZaiSahih
In-book reference: 38:7