Zaynab said, "I went to the house of Zaynab bint Jahsh, the wifeof the Prophet, may Allah bless him and grant him peace, when herbrother had died. She called for perfume and put some on and said, 'ByAllah! I have no need of perfume, but I heard the Messenger of Allah,may Allah bless him and grant him peace, say, 'It is not halal for awoman who trusts in Allah and the Last Day to abstain from adornmentin mourning for someone who has died for more than three nights,except for four months and ten days for a husband.' "
USC-MSA web (English) reference: Book 29, Hadith 102
Arabic reference: Book 29, Hadith 1267