(68) باب الْقُسْطِ وَالأَظْفَارِ لِلْحَادَّةِ
It was narrated from Hafsah, from Umm 'Atiyyah, from the Prophet, that he granted a concession to the woman whose husband has died, allowing her to use Qust and Azfar when purifying herself following her menses.
Reference: Sunan an-Nasa'i 3542
In-book reference: Book 27, Hadith 156
English translation: Vol. 4, Book 27, Hadith 3572