Sunan an-Nasa'i 3525
سنن النسائي#3525SahihIt was narrated from 'Aishah that the Messenger of Allah said:"It is not permissible for a woman to mourn for anyone who dies for more than three days, except for her husband
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 Muslim
In-book reference: 27:137