Sunan an-Nasa'i

Ubadah bin Al-Walid bin 'Ubadah bin As-Samit narrated from Rubayy' bint Mu'awwidh. He said: "I said to her: “Tell me your Hadith.' She said: “I was separated from husband by Khul', then I came to 'Uthman and asked him: What 'Iddah do I have to observe? He said: You do not have to observe any 'Iddah, unless you had intercourse with him recently, in which case you should stay with him until you have menstruated. He said: In that I am following the ruling of the Messenger of Allah concerning Mariam Al-Maghaliyyah, who was married to Thabit bin Qais and was separated by Khul' from him””"