United States. Bureau of Labor Statistics. "Contents," in United States. Bureau of Labor Statistics. "May 2011," PPI Detailed Report (May 2011) : 2-3. https://fraser.stlouisfed.org/title/63/item/21906/toc/161954 , accessed on May 7, 2024.
United States. Bureau of Labor Statistics. "Contents," in United States. Bureau of Labor Statistics. "May 2011," PPI Detailed Report (May 2011) : 2-3. https://fraser.stlouisfed.org/title/63/item/21906/toc/161954 , accessed on May 7, 2024.