Sahih al-Bukhari 314
Narrated `Aisha:
A woman asked the Prophet (ﷺ) about the bath which is taken after finishing from the menses. The Prophet (ﷺ) 
told her what to do and said, "Purify yourself with a piece of cloth scented with musk." The woman 
asked, "How shall I purify myself with it" He said, "Subhan Allah! Purify yourself (with it)." I pulled 
her to myself and said, "Rub the place soiled with blood with it."
حَدَّثَنَا يَحْيَى، قَالَ حَدَّثَنَا ابْنُ عُيَيْنَةَ، عَنْ مَنْصُورِ ابْنِ صَفِيَّةَ، عَنْ أُمِّهِ، عَنْ عَائِشَةَ، أَنَّ امْرَأَةً، سَأَلَتِ النَّبِيَّ صلى الله عليه وسلم عَنْ غُسْلِهَا مِنَ الْمَحِيضِ، فَأَمَرَهَا كَيْفَ تَغْتَسِلُ قَالَ ‏"‏ خُذِي فِرْصَةً مِنْ مِسْكٍ فَتَطَهَّرِي بِهَا ‏"‏‏.‏ قَالَتْ كَيْفَ أَتَطَهَّرُ قَالَ ‏"‏ تَطَهَّرِي بِهَا ‏"‏‏.‏ قَالَتْ كَيْفَ قَالَ ‏"‏ سُبْحَانَ اللَّهِ تَطَهَّرِي ‏"‏‏.‏ فَاجْتَبَذْتُهَا إِلَىَّ فَقُلْتُ تَتَبَّعِي بِهَا أَثَرَ الدَّمِ‏.‏