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Hourly earnings in the United States : another look at unionization, schooling, sickness, and unemployment using PSID data
Chowdhury, Gopa, (1985)
Individual earnings in the U. S. Another Look at unionization, schooling, stickness and unemployment using panel data
Chowdhury, Gopa, (1982)
Fixed effects with interpersonal and intertemporal covariance
Chowdhury, Gopa, (1994)