Ibn Abbas narrated that :
The wife of Thabit bin Qais was granted a Khul from her husband during the time of the Prophet. So the Prophet ordered her to observe an Iddah of a menstruation.
• Jami` at-Tirmidhi, Vol. 2, Book of Divorce, Hadith 1185b
• Jami` at-Tirmidhi, Book of Divorce, Hadith 1185b