Sahih Muslim 749
The Book of Menstruation
وَحَدَّثَنِي أَحْمَدُ بْنُ سَعِيدٍ الدَّارِمِيُّ، حَدَّثَنَا حَبَّانُ، حَدَّثَنَا وُهَيْبٌ، حَدَّثَنَا مَنْصُورٌ، عَنْ أُمِّهِ، عَنْ عَائِشَةَ، أَنَّ امْرَأَةً، سَأَلَتِ النَّبِيَّ صلى الله عليه وسلم كَيْفَ أَغْتَسِلُ عِنْدَ الطُّهْرِ فَقَالَ " خُذِي فِرْصَةً مُمَسَّكَةً فَتَوَضَّئِي بِهَا " . ثُمَّ ذَكَرَ نَحْوَ حَدِيثِ سُفْيَانَ .
A'isha reported:A woman asked the Messenger of Allah (ﷺ) how he should wash herself after the menstrual period. He (the Holy Prophet) said: Take a cotton with musk and purity yourself, and the rest of the hadith was narrated like that of Sufyan
Text from the public-domain hadith-api dataset. Numbering follows that dataset and can differ by a few from some printed editions — check the wording, not only the number.