There was a disagreement between Ibrahim Nakha'i (may Allah have mercy on him) and Sha'bi (may Allah have mercy on him). One said: "She should complete the waiting period ('iddah) of the first husband." The other said: "She should complete the waiting period of the second husband." Ibrahim (may Allah have mercy on him) said: "If you say this, you will be caught in a dilemma."
Hadith Referenceسنن سعید بن منصور / كتاب النكاح / 1878
Hadith Takhrij«أخرجه سعيد بن منصور فى «سننه» ترقيم الدرالسلفية برقم:، 701، 702، 703»