Sunan an-Nasai Book 1, Hadith 108

أَخْبَرَنَا عَمْرُو بْنُ عَلِيٍّ، وَحُمَيْدُ بْنُ مَسْعَدَةَ، عَنْ يَزِيدَ، - وَهُوَ ابْنُ زُرَيْعٍ - قَالَ حَدَّثَنَا حُمَيْدٌ، قَالَ حَدَّثَنَا بَكْرُ بْنُ عَبْدِ اللَّهِ الْمُزَنِيُّ، عَنْ حَمْزَةَ بْنِ الْمُغِيرَةِ بْنِ شُعْبَةَ، عَنْ أَبِيهِ، قَالَ تَخَلَّفَ رَسُولُ اللَّهِ صلى الله عليه وسلم فَتَخَلَّفْتُ مَعَهُ فَلَمَّا قَضَى حَاجَتَهُ قَالَ ‏ "‏ أَمَعَكَ مَاءٌ ‏"‏ ‏.‏ فَأَتَيْتُهُ بِمِطْهَرَةٍ فَغَسَلَ يَدَيْهِ وَغَسَلَ وَجْهَهُ ثُمَّ ذَهَبَ يَحْسُرُ عَنْ ذِرَاعَيْهِ فَضَاقَ كُمُّ الْجُبَّةِ فَأَلْقَاهُ عَلَى مَنْكِبَيْهِ فَغَسَلَ ذِرَاعَيْهِ وَمَسَحَ بِنَاصِيَتِهِ وَعَلَى الْعِمَامَةِ وَعَلَى خُفَّيْهِ ‏.‏

It was narrated from Hamzah bin Al-Mughirah bin Shu'bah that his father said:"The Messenger of Allah (ﷺ) stayed behind, and I stayed with him. When he had relieved himself he said: 'Do you have any water with you?' I brought some water to him, and he washed his hands and face, then he started trying to uncover his arms, but the sleeves of his Jubbah were too tight, so he threw it over his shoulders and washed his arms and wiped over his forehead and 'Imamah, and over his Khuff