Musannaf Ibn Abi Shaybah

Hazrat Salih bin Muslim, may Allah have mercy on him, says that if a person divorces his wife and then, during her waiting period (‘iddah), another man marries her, what is the ruling? He replied that Hazrat Umar, may Allah be pleased with him, says that separation will be enforced between the two. And she will begin a new waiting period (‘iddah) from the second husband, and her dowry (mahr) will be given from the public treasury (bait-ul-mal). The second husband can never marry her, and the first husband may send a marriage proposal. Hazrat Ali, may Allah be pleased with him, says that separation will be enforced between her and her husband. She will complete the first waiting period (‘iddah) and then observe a new waiting period from this husband. That man himself will give her dowry (mahr), and both of them may send her a marriage proposal.