United States. Bureau of Labor Statistics. "Contents," in United States. Bureau of Labor Statistics. "September 1997," PPI Detailed Report (September 1997) : 3-4. https://fraser.stlouisfed.org/title/63/item/21743/toc/81854 , accessed on May 2, 2024.
United States. Bureau of Labor Statistics. "Contents," in United States. Bureau of Labor Statistics. "September 1997," PPI Detailed Report (September 1997) : 3-4. https://fraser.stlouisfed.org/title/63/item/21743/toc/81854 , accessed on May 2, 2024.