The Book of Divorce
18/9. Chapter:
The Obligation to mourn during the 'Iddah following the death of one's husband, but it is forbidden to mourn for more than three days in other cases
Sahih Muslim
وَحَدَّثَنَاهُ شَيْبَانُ بْنُ فَرُّوخَ، حَدَّثَنَا عَبْدُ الْعَزِيزِ، - يَعْنِي ابْنَ مُسْلِمٍ - حَدَّثَنَا عَبْدُ، اللَّهِ بْنُ دِينَارٍ عَنْ نَافِعٍ، بِإِسْنَادِ حَدِيثِ اللَّيْثِ . مِثْلَ رِوَايَتِهِ .
A hadith like this is transmitted on the authority of Nafi'.
Reference : Sahih Muslim 1490bIn-book reference : Book 18, Hadith 81USC-MSA web (English) reference : Book 9, Hadith 3546