Hadith 10:1036
Abu Bakr narrated to us, he said: Ibn ‘Ulayyah narrated to us, from Layth, from ‘Ata’ and Tawus, they both said: The waiting period (‘iddah) of the umm al-walad (a slave woman who has borne a child for her master) and the concubine (surriyah), if her master dies leaving her behind, is two months and five nights.
حدثنا أبو بكر قال نا بن علية عن ليث عن عطاء وطاوس قالا عدة أم الولد والسرية إذا توفي عنها سيدها شهران وخمس ليال