Muwatta Malik 1267

Zaynab said, "I went to the house of Zaynab bint Jahsh, the wife of the Prophet, (ﷺ), when her brother had died. She called for perfume and put some on and said, 'By Allah! I have no need of perfume, but I heard the Messenger of Allah, (ﷺ), say, 'It is not halal for a woman who trusts in Allah and the Last Day to abstain from adornment in mourning for someone who has died for more than three nights, except for four months and ten days for a husband.' "