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Bartoszynski has written a "simplified" account of Shelah's proof of consistency of "Covering of null ideal has countable cofinality" in his article in handbook. In a subsequent paper, Shelah also constructed a model of "The null ideal restricted to some non null set is $\omega_1$-saturated". The proof uses iterations of "partial random reals" and makes several references to his countable cofinality paper and I could not follow it starting page 17. Has someone written a simplified account of this proof that maybe does not refer to Shelah's countable cofinality paper?

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