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Non-linearities and fractional integration in the US unemployment rate
Caporale, Guglielmo Maria, (2004)
Complementarity of labor market institutions, equilibrium unemployment and the propagation of business cycles
Burda, Michael C., (2001)
A Test of the 'Krugman Hypothesis' for the United States, Britain, and Western Germany
Puhani, Patrick A., (2003)