United States. Bureau of Economic Analysis. "U.S. International Trade in Goods and Services, March 2007 : Highlights: March 2007 Trade Gap Is $63.9 Billion, BEA 07-20, CB 07-65, FT-900 (07-03)," Bureau of Economic Analysis (BEA) News Releases (May 10, 2007). https://fraser.stlouisfed.org/title/6148/item/598961/content/pdf/bea_newsreleases_20070510_highlights, accessed on May 15, 2025.