Language:
كتاب النكاح
67
Wedlock, Marriage (Nikaah)
(29)
Chapter: Ash-Shighar. (Exchange of daughters or sisters in marriage without paying Mahr)
(28)
باب الشِّغَارِ

Narrated Ibn `Umar:

Allah's Messenger (ﷺ) forbade Ash-Shighar, which means that somebody marries his daughter to somebody else, and the latter marries his daughter to the former without paying Mahr.

حَدَّثَنَا عَبْدُ اللَّهِ بْنُ يُوسُفَ، أَخْبَرَنَا مَالِكٌ، عَنْ نَافِعٍ، عَنِ ابْنِ عُمَرَ ـ رضى الله عنهما ـ أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم نَهَى عَنِ الشِّغَارِ، وَالشِّغَارُ أَنْ يُزَوِّجَ الرَّجُلُ ابْنَتَهُ عَلَى أَنْ يُزَوِّجَهُ الآخَرُ ابْنَتَهُ، لَيْسَ بَيْنَهُمَا صَدَاقٌ‏.‏
Reference : Sahih al-Bukhari 5112
In-book reference : Book 67, Hadith 49
USC-MSA web (English) reference : Vol. 7, Book 62, Hadith 47
  (deprecated numbering scheme)