J. Bradford DeLong and Lawrence H. Summers (1986), "The Changing Cyclical Variability of Economic Activity in the United States"
J. Bradford DeLong and Lawrence H. Summers (1986), "The Changing Cyclical Variability of Economic Activity in the United States," in Robert J. Gordon, ed., The American Business Cycle: Continuity and Change (Chicago, IL: University of Chicago Press for the National Bureau of Economic Research), pp. 679-719.