United States. Bureau of Labor Statistics. "Durable Manufacturing Sector - Appendix - Quarterly Data," in United States. Bureau of Labor Statistics. "Third Quarter 1992 [Preliminary]," Productivity and Costs (November 5, 1992) : 16-16. https://fraser.stlouisfed.org/title/131/item/55828/toc/465899 , accessed on May 3, 2024.