United States. Bureau of Economic Analysis. "National Income and Product Accounts : Preliminary Second Quarter 1987 (GNP), Revised Estimates: 1984 Through First Quarter 1987, BEA 87-36," Bureau of Economic Analysis (BEA) News Releases (July 24, 1987). https://fraser.stlouisfed.org/title/6148/item/596683, accessed on March 21, 2025.