Sayyiduna Ibn Umar (may Allah be pleased with them both), regarding a slave woman who is the wife of a free man, says: "She will become separated (bainah) through two divorces, and will observe the waiting period ('iddah) for two menstrual cycles. And when a free woman is the wife of a slave, she will become separated through two divorces and will observe the waiting period for three menstrual cycles." This narration has also been transmitted by other narrators as a mawquf (companion's statement) narration, and this is correct. With another chain, this narration has been transmitted as a marfu' (Prophet's statement) hadith, but this narration is munkar (rejected) and is not established from two aspects: one is that the narrator named 'Atiyyah is weak, while Salim and Nafi' are more reliable and transmit more authentic narrations; the second aspect is that 'Amr bin Shayb is weak in hadith, and his narration cannot be used as evidence. And Allah knows best.