Sahih Muslim
The Book Pertaining to the Oath, for Establishing the Responsibility of Murders, Fighting, Requital and Blood-Wit (Kitab Al-Kitab Al-Qasama wal-Muharaba wal-Qisas wal-Diyat)
Book Number: 016 / Hadith Number: 4174
Miswar b. Makhrama reported that 'Umar b. Khattab consulted people about the diyat of abortion of an unboam child. Mughira b. Shu'ba said: I bear witness to the fact that Allah's Messenger (may peace be upon him) gave judgment about it that a good quality of slave or female slave should be given for it. Thereupon 'Umar said: Bring one who may bear witness to you. Then Muhammad b. Maslama bore witness to him.