United States. Bureau of Labor Statistics. "Contents," in United States. Bureau of Labor Statistics. "April 1983," PPI Detailed Report (April 1983) : 3-3. https://fraser.stlouisfed.org/title/63/item/21569/toc/422025 , accessed on April 18, 2024.
United States. Bureau of Labor Statistics. "Contents," in United States. Bureau of Labor Statistics. "April 1983," PPI Detailed Report (April 1983) : 3-3. https://fraser.stlouisfed.org/title/63/item/21569/toc/422025 , accessed on April 18, 2024.