Language:
كتاب الوضوء
4
Ablutions (Wudu')
(31)
Chapter: While performing ablution or taking a bath one should start from the right side of the body
(31)
باب التَّيَمُّنِ فِي الْوُضُوءِ وَالْغُسْلِ

Narrated Um-`Atiya:

That the Prophet (ﷺ) 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."

حَدَّثَنَا مُسَدَّدٌ، قَالَ حَدَّثَنَا إِسْمَاعِيلُ، قَالَ حَدَّثَنَا خَالِدٌ، عَنْ حَفْصَةَ بِنْتِ سِيرِينَ، عَنْ أُمِّ عَطِيَّةَ، قَالَتْ قَالَ النَّبِيُّ صلى الله عليه وسلم لَهُنَّ فِي غُسْلِ ابْنَتِهِ ‏ "‏ ابْدَأْنَ بِمَيَامِنِهَا وَمَوَاضِعِ الْوُضُوءِ مِنْهَا ‏"‏‏.‏
Reference : Sahih al-Bukhari 167
In-book reference : Book 4, Hadith 33
USC-MSA web (English) reference : Vol. 1, Book 4, Hadith 168
  (deprecated numbering scheme)