United States. Bureau of Labor Statistics. "Mining," in United States. Bureau of Labor Statistics. "February 1984," PPI Detailed Report (February 1984) : 143-143. https://fraser.stlouisfed.org/title/63/item/21579/toc/59640 , accessed on May 4, 2024.
United States. Bureau of Labor Statistics. "Mining," in United States. Bureau of Labor Statistics. "February 1984," PPI Detailed Report (February 1984) : 143-143. https://fraser.stlouisfed.org/title/63/item/21579/toc/59640 , accessed on May 4, 2024.