Language:
كتاب النكاح
67  
Wedlock, Marriage (Nikaah)
(119)
Chapter: A woman should not look at or touch the body of another woman to describe to her husband
(118)
باب لاَ تُبَاشِرُ الْمَرْأَةُ الْمَرْأَةَ فَتَنْعَتَهَا لِزَوْجِهَا
Sahih al-Bukhari 5240

Narrated `Abdullah bin Mas`ud:

The Prophet (ﷺ) said, "A woman should not look at or touch another woman to describe her to her husband in such a way as if he was actually looking at her."

حَدَّثَنَا مُحَمَّدُ بْنُ يُوسُفَ، حَدَّثَنَا سُفْيَانُ، عَنْ مَنْصُورٍ، عَنْ أَبِي وَائِلٍ، عَنْ عَبْدِ اللَّهِ بْنِ مَسْعُودٍ ـ رضى الله عنه ـ قَالَ قَالَ النَّبِيُّ صلى الله عليه وسلم ‏ "‏ لاَ تُبَاشِرِ الْمَرْأَةُ الْمَرْأَةَ فَتَنْعَتَهَا لِزَوْجِهَا، كَأَنَّهُ يَنْظُرُ إِلَيْهَا ‏"‏‏.‏
Reference : Sahih al-Bukhari 5240
In-book reference : Book 67, Hadith 173
USC-MSA web (English) reference : Vol. 7, Book 62, Hadith 167
  (deprecated numbering scheme)