Sunan an-Nasa'i, Volume 4, Book 26, Hadith 3304 (DarusSalam) ⓘ
It was narrated from 'Aishah that the Prophet said: "What becomes unlawful (for marriage) through breast-feeding is that which becomes unlawful through lineage."
أَخْبَرَنَا مُحَمَّدُ بْنُ بَشَّارٍ، قَالَ حَدَّثَنَا يَحْيَى، عَنْ مَالِكٍ، عَنْ عَبْدِ اللَّهِ بْنِ أَبِي بَكْرٍ، عَنْ عَمْرَةَ، عَنْ عَائِشَةَ، عَنِ النَّبِيِّ صلى الله عليه وسلم قَالَ " يَحْرُمُ مِنَ الرَّضَاعِ مَا يَحْرُمُ مِنَ النَّسَبِ " .
also referenced under: Hadith 3302 (Reference) & Book 26, Hadith 107 (In-Book)