Maliks Muwatta Book 28, Hadith Number 55.
Section : Marriage in General.
Yahya related to me from Malik from Rabia ibn Abd ar-Rahman that al-Qasim ibn Muhammad and Urwa ibn az-Zubayr gave the same judgement to al-Walid ibn Abd al-Malik in the year of his arrival in Madina except that al-Qasim ibn Muhammad said that he divorced his wife on various occasions. (i.e. not at one time).