The paper contains a simple proof of the classical Hahn decomposition theorem for charges and, as a corollary, an explicit measurable in parameter construction of a Radon-Nikodym derivative of one measure by another.
A simple proof of Bailey's very-well-poised 6-psi-6 summation
Differentiation of measures on a non-separable space, and the Radon-Nikodym theorem
A simple proof of the $A_2$ conjecture
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