Al-Kāfi - Volume 5 > Marriage with Slave Girls
Hadith #3

3- مُحَمَّدُ بْنُ يَحْيَى عَنْ أَحْمَدَ بْنِ مُحَمَّدِ بْنِ عِيسَى عَنْ مُحَمَّدِ بْنِ إِسْمَاعِيلَ قَالَ سَأَلْتُ أَبَا الْحَسَنِ (عَلَيْهِ السَّلام) هَلْ لِلرَّجُلِ أَنْ يَتَمَتَّعَ مِنَ الْمَمْلُوكَةِ بِإِذْنِ أَهْلِهَا وَلَهُ امْرَأَةٌ حُرَّةٌ قَالَ نَعَمْ إِذَا رَضِيَتِ الْحُرَّةُ قُلْتُ فَإِنْ أَذِنَتِ الْحُرَّةُ يَتَمَتَّعُ مِنْهَا قَالَ نَعَمْ. وَرُوِيَ أَيْضاً أَنَّهُ لا يَجُوزُ أَنْ يُتَمَتَّعَ بِالأمَةِ عَلَى الْحُرَّةِ.

3. Muhammad ibn Yahya has narrated from Ahmad ibn Muhammad ibn ‘Isa from Muhammad ibn ‘Isma’il who has said the following: “I once asked abu al-Hassan, ‘Alayhi al-Salam, ‘A man has a free wife; if he can marry a slave-girl in the manner of al-Mut‘ah (advantageous marriage) by the permission of her master.’ He (the Imam) said, ‘Yes, he can do so.’ It also is narrated that marriage of a slave-girl in the manner of al-Mut‘ah (advantageous marriage) when one has a free wife is not permissible.’”