United States. Bureau of Labor Statistics. "Contents," in United States. Bureau of Labor Statistics. "February 1987," PPI Detailed Report (February 1987) : 3-3. https://fraser.stlouisfed.org/title/63/item/21615/toc/390122 , accessed on May 7, 2024.
United States. Bureau of Labor Statistics. "Contents," in United States. Bureau of Labor Statistics. "February 1987," PPI Detailed Report (February 1987) : 3-3. https://fraser.stlouisfed.org/title/63/item/21615/toc/390122 , accessed on May 7, 2024.