Sunan an-Nasa'i 3536
سنن النسائي#3536SahihIt was narrated from Umm 'Atiyyah that the Prophet said:"It is not permissible for a woman who believes in Allah and the Last Day, to mourn for anyone who dies for more than three days, except for a husband; she should not use kohl, dye nor wear dyed clothes
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 ZaiIsnaad Sahih
In-book reference: 27:150