United States. Bureau of Economic Analysis. "U.S. International Trade in Goods and Services: December 2007, BEA 08-05, CB 08-27, FT-900 (07-12),"
Bureau of Economic Analysis (BEA) News Releases
(February 14, 2008).
https://fraser.stlouisfed.org/title/6148/item/600438, accessed on June 24, 2025.