United States. Bureau of Labor Statistics. "April 1997," PPI Detailed Report (April 1997). https://fraser.stlouisfed.org/title/63/item/21739, accessed on April 19, 2024.
United States. Bureau of Labor Statistics. "April 1997," PPI Detailed Report (April 1997). https://fraser.stlouisfed.org/title/63/item/21739, accessed on April 19, 2024.