United States. Bureau of Labor Statistics. "Contents," in United States. Bureau of Labor Statistics. "May 1998," PPI Detailed Report (May 1998) : 3-4. https://fraser.stlouisfed.org/title/63/item/21751/toc/136732 , accessed on April 25, 2024.
United States. Bureau of Labor Statistics. "Contents," in United States. Bureau of Labor Statistics. "May 1998," PPI Detailed Report (May 1998) : 3-4. https://fraser.stlouisfed.org/title/63/item/21751/toc/136732 , accessed on April 25, 2024.