United States. Bureau of Labor Statistics. "Contents," in United States. Bureau of Labor Statistics. "October 1981," PPI Detailed Report (October 1981) : 3-3. https://fraser.stlouisfed.org/title/63/item/21551/toc/46139 , accessed on April 23, 2024.
United States. Bureau of Labor Statistics. "Contents," in United States. Bureau of Labor Statistics. "October 1981," PPI Detailed Report (October 1981) : 3-3. https://fraser.stlouisfed.org/title/63/item/21551/toc/46139 , accessed on April 23, 2024.