Muwatta Malik #1513
Judgements
The Arabic includes the chain of narration (sanad) and the collector's commentary; the English translation shows the Prophet's words only.
قَالَ يَحْيَى قَالَ مَالِكٌ عَنِ ابْنِ شِهَابٍ، عَنْ سَالِمِ بْنِ عَبْدِ اللَّهِ بْنِ عُمَرَ، عَنْ أَبِيهِ، أَنَّ عُمَرَ بْنَ الْخَطَّابِ، قَالَ مَا بَالُ رِجَالٍ يَطَئُونَ وَلاَئِدَهُمْ ثُمَّ يَعْزِلُوهُنَّ لاَ تَأْتِينِي وَلِيدَةٌ يَعْتَرِفُ سَيِّدُهَا أَنْ قَدْ أَلَمَّ بِهَا إِلاَّ أَلْحَقْتُ بِهِ وَلَدَهَا فَاعْزِلُوا بَعْدُ أَوِ اتْرُكُوا .
Yahya said that Malik related from Ibn Shihab from Salim ibn
Abdullah ibn Umar from his father that Umar ibn al-Khattab said,
"What's the matter with men who have intercourse with their slave-
girls and then dismiss them? No slave-girl comes to me whose master
confesses that he has had intercourse with her but that I connect her
child to him, whether or not he has practised coitus interruptus or
stopped having intercourse with her."
About Muwatta Malik
This hadith is #1513 from Muwatta Malik, in the Book of Judgements.