مُوَطَّأُ مَالِكٍ
Muwatta Malik 1481
Setting Free and Wala'
وَحَدَّثَنِي مَالِكٌ، عَنْ نَافِعٍ، عَنْ عَبْدِ اللَّهِ بْنِ عُمَرَ، أَنَّهُ أَعْتَقَ وَلَدَ زِنًا وَأُمَّهُ .
Malik related to me from Nafi that Abdullah ibn Umar freed an illegitimate child and its mother.
Arabic/English book reference: Book 38, Hadith 16