United States. Bureau of Economic Analysis. "U.S. International Trade in Goods and Services: April 2014 : U.S. International Trade in Goods and Services: Annual Revision 2013, BEA 14-23, CB 14-99, FT-900 (14-04),"
Bureau of Economic Analysis (BEA) News Releases
(June 4, 2014).
https://fraser.stlouisfed.org/title/6148/item/602103/content/pdf/bea_newsreleases_20140604_annual-revision, accessed on June 16, 2025.