Where does a woman divorced with three simultaneous pronouncements of divorce observe her iddah?

A woman divorced irrevocably (three times) has no right to maintenance or housing, unless she is pregnant, based on the statement of Fatimah bint Qays: "My husband divorced me three times during the time of the Prophet, peace and blessings be upon him, and he did not grant me maintenance or housing." As for an irrevocably divorced woman who is pregnant, she is unanimously entitled to maintenance and housing, based on the verse: "And if they should be pregnant, then spend on them until they deliver their burden." The preponderant opinion is that of Imam Ahmad, may Allah have mercy on him, which states that an irrevocably divorced woman has no right to maintenance or housing unless she is pregnant.