Sunan an-Nasa'i 1998
سنن النسائي#1998SahihIt was narrated that Abu Sa'eed said:"The Messenger of Allah said: 'If you see a funeral, then stand up, and whoever follows it, then let him not sit down until (the body) is placed in the grave
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 ZaiHasan
In-book reference: 21:181