Musannaf Ibn Abi Shayba 13:2729

Abu Bakr narrated to us, he said: Waki’ narrated to us, he said: Isma’il bin Abi Khalid narrated to us, he said: Al-Mughirah bin Sa’id asked Al-Sha’bi: "Is the testimony of a man and two women permissible in divorce?" He said: "Yes."