Musannaf Ibn Abi Shaybah 19578 — Those who said she receives half

Ikrimah (may Allah have mercy on him) and al-Hasan (may Allah have mercy on him) said: If a man separated from his wife by khul', then married her during her waiting period ('iddah), then divorced her before consummating the marriage, the woman will receive half the dower, and she will complete the remainder of her waiting period.