United States. Department of Commerce. "U.S. International Transactions: Second Quarter 2013 : Tables, BEA 13-43," United States Department of Commerce News (September 19, 2013). https://fraser.stlouisfed.org/title/6148/item/601566/content/xls/bea_newsreleases_20130919_tables-only-excel, accessed on May 30, 2026.