Sahih al-Bukhari 1280
صحيح البخاري#1280SahihNarrated Zainab bint Abi Salama:When the news of the death of Abu Sufyan reached from Sham, Um Habiba on the third day, asked for a yellow perfume and scented her cheeks and forearms and said, "No doubt, I would not have been in need of this, had I not heard the Prophet (ﷺ) saying: "It is not legal for a woman who believes in Allah and the Last Day to mourn for more than three days for any dead person except her husband, for whom she should mourn for four months and ten days
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Every narration in Sahih al-Bukhari is accepted as Sahih (authentic) by the established status of the book.
In-book reference: 23:41