حَدَّثَنَا أَحْمَدُ بْنُ يُونُسَ، حَدَّثَنَا زُهَيْرٌ، عَنْ دَاوُدَ بْنِ عَبْدِ اللَّهِ، ح وَحَدَّثَنَا مُسَدَّدٌ، حَدَّثَنَا أَبُو عَوَانَةَ، عَنْ دَاوُدَ بْنِ عَبْدِ اللَّهِ، عَنْ حُمَيْدٍ الْحِمْيَرِيِّ، قَالَ لَقِيتُ رَجُلاً صَحِبَ النَّبِيَّ صلى الله عليه وسلم أَرْبَعَ سِنِينَ كَمَا صَحِبَهُ أَبُو هُرَيْرَةَ قَالَ نَهَى رَسُولُ اللَّهِ صلى الله عليه وسلم أَنْ تَغْتَسِلَ الْمَرْأَةُ بِفَضْلِ الرَّجُلِ أَوْ يَغْتَسِلَ الرَّجُلُ بِفَضْلِ الْمَرْأَةِ - زَادَ مُسَدَّدٌ - وَلْيَغْتَرِفَا جَمِيعًا ‏.‏

Narrated Humayd al-Himyari: Humayd al-Himyari reported: I met a person (among the Companion of Prophet) who remained in the company of the Prophet (PBUH)for four years as AbuHurayrah remained in his company. He reported: The Messenger of Allah (PBUH) forbade that the female should wash with the water left over by the male, and that the male should wash with the left-over of the female. The version of Musaddad adds: "That they both take the handful of water together." Translation Not Available

Book Ref: Sunan Abi Dawud Book 1 Hadith 81
Web Ref:  Sunan Abi Dawud Book 1 Hadith 81