APA
Freeman R. B., Schettkat R., . (2000). The role of wage and skill differences in US-German employment differences. Cambridge, Mass: National Bureau of Economic Research.
Chicago
Freeman Richard B, Schettkat Ronald, . 2000. The role of wage and skill differences in US-German employment differences. Cambridge, Mass: National Bureau of Economic Research.
Harvard
Freeman R. B., Schettkat R., . (2000). The role of wage and skill differences in US-German employment differences. Cambridge, Mass: National Bureau of Economic Research.
MLA
Freeman Richard B, Schettkat Ronald, . The role of wage and skill differences in US-German employment differences. Cambridge, Mass: National Bureau of Economic Research. 2000.