Abu Dawud
Prescribed Punishments
Book Number: 033 / Hadith Number: 4446
Narated By Salamah ibn al-Muhabbaq : A similar tradition (to the No. 4445) has also been transmitted by Salamah ibn al-Muhabbaq from the Prophet (pbuh).
This version has: If she asked her to have intercourse with her voluntarily, then she and a similar slave-girl would be given to her mistress from his property.