United States. Bureau of Economic Analysis. "U.S. International Trade in Goods and Services: June 2015, BEA 15-37, CB 15-135, FT-900 (15-06),"
Bureau of Economic Analysis (BEA) News Releases
(August 5, 2015).
https://fraser.stlouisfed.org/title/6148/item/602255, accessed on June 13, 2025.