United States. Department of Commerce. "U.S. International Trade in Goods and Services: April 2006, CB 06-86, BEA 06-25, FT-900 (06-04),"
United States Department of Commerce News
(June 9, 2006).
https://fraser.stlouisfed.org/title/6148/item/598036, accessed on June 1, 2026.