Sahih Al Bukhari (167)

حَدَّثَنَا مُسَدَّدٌ، قَالَ: حَدَّثَنَا إِسْمَاعِيلُ، قَالَ: حَدَّثَنَا خَالِدٌ، عَنْ حَفْصَةَ بِنْتِ سِيرِينَ، عَنْ أُمِّ عَطِيَّةَ، قَالَتْ: قَالَ النَّبِيُّ صَلَّى اللهُ عَلَيْهِ وَسَلَّمَ لَهُنَّ فِي غَسْلِ ابْنَتِهِ: "ابْدَأْنَ بِمَيَامِنِهَا وَمَوَاضِعِ الوُضُوءِ مِنْهَا "

Um `Atiyyah (may Allah be pleased with her) narrated that the Prophet (peace be upon him) at the time of washing his deceased daughter had said to them: "Start from the right side beginning with those parts which are washed in ablution."