Language:
كتاب الوضوء
4  
Ablutions (Wudu')
(43)
Chapter: The performance of ablution by a man along with his wife. The utilization of water remaining after a woman has performed ablution. Umar performed ablution with warm water and with water brought from the house of a Christian woman
(43)
باب وُضُوءِ الرَّجُلِ مَعَ امْرَأَتِهِ وَفَضْلِ وَضُوءِ الْمَرْأَةِ‏
Sahih al-Bukhari 193
Narrated 'Abdullah bin 'Umar:
"During the lifetime of Allah's Messenger (ﷺ) men and women used to perform ablution together."
حَدَّثَنَا عَبْدُ اللَّهِ بْنُ يُوسُفَ، قَالَ أَخْبَرَنَا مَالِكٌ، عَنْ نَافِعٍ، عَنْ عَبْدِ اللَّهِ بْنِ عُمَرَ، أَنَّهُ قَالَ كَانَ الرِّجَالُ وَالنِّسَاءُ يَتَوَضَّئُونَ فِي زَمَانِ رَسُولِ اللَّهِ صلى الله عليه وسلم جَمِيعًا‏.‏
Reference : Sahih al-Bukhari 193
In-book reference : Book 4, Hadith 59
USC-MSA web (English) reference : Vol. 1, Book 4, Hadith 192
  (deprecated numbering scheme)