United States. Bureau of Labor Statistics. "Price Movements," in United States. Bureau of Labor Statistics. "April 1999," PPI Detailed Report (April 1999) : 5-7. https://fraser.stlouisfed.org/title/63/item/21763/toc/231547 , accessed on May 2, 2024.
United States. Bureau of Labor Statistics. "Price Movements," in United States. Bureau of Labor Statistics. "April 1999," PPI Detailed Report (April 1999) : 5-7. https://fraser.stlouisfed.org/title/63/item/21763/toc/231547 , accessed on May 2, 2024.