United States. Bureau of Labor Statistics. "Text," in United States. Bureau of Labor Statistics. "Productivity and Costs in Nonfinancial Corporations (and Revised Figures for the Private Economy) : Second Quarter 1973," Productivity and Costs (August 24, 1973) : 1-4. https://fraser.stlouisfed.org/title/131/item/55853/toc/494597 , accessed on May 2, 2024.