Muwatta Malik #1323
Divorce
The Arabic includes the chain of narration (sanad) and the collector's commentary; the English translation shows the Prophet's words only.
وَحَدَّثَنِي عَنْ مَالِكٍ، عَنْ نَافِعٍ، عَنْ صَفِيَّةَ بِنْتِ أَبِي عُبَيْدٍ، عَنْ عَائِشَةَ، وَحَفْصَةَ، زَوْجَىِ النَّبِيِّ صلى الله عليه وسلم أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ " لاَ يَحِلُّ لاِمْرَأَةٍ تُؤْمِنُ
Yahya related to me from Malik from Nafi from Safiyya bint Abi
Ubayd from A'isha and Hafsa, the wives of the Prophet, may Allah bless
him and grant him peace, that the Messenger of Allah, may Allah bless
him and grant him peace, said, "It is not halal for a woman in
mourning for someone who has died, if she trusts in Allah and the Last
Day, to abstain from adornment for more than three nights, except for
a husband."
About Muwatta Malik
This hadith is #1323 from Muwatta Malik, in the Book of Divorce.