Sunan Abi Dawud, Book 32, Hadith 4101 (USC-MSA) ⓘ
Narrated 'Amr b. Suh'aib: On his father's authority, said that his grandfather reported the Prophet said: When one of you marries his male-slave to his slave-woman, he should not look at her private parts.
حَدَّثَنَا مُحَمَّدُ بْنُ عَبْدِ اللَّهِ بْنِ الْمَيْمُونِ، حَدَّثَنَا الْوَلِيدُ، عَنِ الأَوْزَاعِيِّ، عَنْ عَمْرِو بْنِ شُعَيْبٍ، عَنْ أَبِيهِ، عَنْ جَدِّهِ، عَنِ النَّبِيِّ صلى الله عليه وسلم قَالَ " إِذَا زَوَّجَ أَحَدُكُمْ عَبْدَهُ أَمَتَهُ فَلاَ يَنْظُرْ إِلَى عَوْرَتِهَا " .
also referenced under: Hadith 4113 (DarusSalam) & Hadith 4101 (Hasan)