Sunan Ibn Majah 580
It was narrated that 'Aishah said:
"The Messenger of Allah used to have a bath to cleanse himself from sexual impurity, then he would warm himself with me before I had the bath."
حَدَّثَنَا أَبُو بَكْرِ بْنُ أَبِي شَيْبَةَ، حَدَّثَنَا شَرِيكٌ، عَنْ حُرَيْثٍ، عَنِ الشَّعْبِيِّ، عَنْ مَسْرُوقٍ، عَنْ عَائِشَةَ، قَالَتْ كَانَ رَسُولُ اللَّهِ ـ صلى الله عليه وسلم ـ يَغْتَسِلُ مِنَ الْجَنَابَةِ ثُمَّ يَسْتَدْفِئُ بِي قَبْلَ أَنْ أَغْتَسِلَ ‏.‏