United States. Bureau of Labor Statistics. "Contents," in United States. Bureau of Labor Statistics. "August 1990," PPI Detailed Report (August 1990) : 3-4. https://fraser.stlouisfed.org/title/63/item/21659/toc/201489 , accessed on May 8, 2024.
United States. Bureau of Labor Statistics. "Contents," in United States. Bureau of Labor Statistics. "August 1990," PPI Detailed Report (August 1990) : 3-4. https://fraser.stlouisfed.org/title/63/item/21659/toc/201489 , accessed on May 8, 2024.