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Improving the LIS Income Measure: Microdata Estimates of the Size Distribution of Cash and Noncash Income in Eight Countries
Smeeding, Timothy, (1987)
Noncash Income, Living Standards, and Inequality: Evidence from the Luxembourg Income Study
Wolfson, Michael, (1992)
Polarization and the decline of the middle class : Canada and the US
Foster, James E., (2009)