Sunan Ibn Majah #371 · The Book of Purification and its Sunnah

Sunan Ibn MajahIt was narrated from Ibn 'Abbas that
Sunan Ibn Majah · Book 1 · The Book of Purification and its Sunnah
Sunan Ibn Majah · كتاب 1 · كتاب الطهارة وسننها
One of the wives of the Prophet took a bath to cleanse herself from sexual impurity, then the Prophet performed ablution and had a bath with the water left over from her ablution
حَدَّثَنَا عَلِيُّ بْنُ مُحَمَّدٍ، حَدَّثَنَا وَكِيعٌ، عَنْ سُفْيَانَ، عَنْ سِمَاكِ بْنِ حَرْبٍ، عَنْ عِكْرِمَةَ، عَنِ ابْنِ عَبَّاسٍ، أَنَّ امْرَأَةً، مِنْ أَزْوَاجِ النَّبِيِّ ـ صلى الله عليه وسلم ـ اغْتَسَلَتْ مِنْ جَنَابَةٍ فَتَوَضَّأَ أَوِ اغْتَسَلَ النَّبِيُّ ـ صلى الله عليه وسلم ـ مِنْ فَضْلِ وَضُوئِهَا ‏.‏
Reference : Sunan Ibn Majah 371In-book reference : Book 1, Hadith 105