أَخْبَرَنَا مُحَمَّدُ بْنُ يَحْيَى بْنِ مُحَمَّدٍ، قَالَ حَدَّثَنَا مُحَمَّدُ بْنُ مُوسَى بْنِ أَعْيَنَ، قَالَ حَدَّثَنَا أَبِي، عَنْ عَبْدِ الْمَلِكِ بْنِ أَبِي سُلَيْمَانَ، عَنْ عَطَاءٍ، قَالَ حَدَّثَتْنِي أُمُّ هَانِئٍ، أَنَّهَا دَخَلَتْ عَلَى النَّبِيِّ صلى الله عليه وسلم يَوْمَ فَتْحِ مَكَّةَ وَهُوَ يَغْتَسِلُ قَدْ سَتَرَتْهُ بِثَوْبٍ دُونَهُ فِي قَصْعَةٍ فِيهَا أَثَرُ الْعَجِينِ ‏‏.‏‏ قَالَتْ فَصَلَّى الضُّحَى فَمَا أَدْرِي كَمْ صَلَّى حِينَ قَضَى غُسْلَهُ ‏‏.‏‏

Umm Hani' narrated that she entered upon the Prophet (PBUH) on the day of the Conquest of Makkah, when he was performing Ghusl - while a garment was screening him - from a vessel in which were traces of dough. She said: He prayed Ad-Duha - but I do not know how many Rak'ahs he prayed - after he finished Ghusl.'" Translation Not Available

Book Ref: Sunan An Nisai Book 4 Hadith 415
Web Ref:  Sunan An Nisai Vol 1 Book 4 Hadith 415