http://Bridging to Brexit: Insights from European SMEs, Corporates and Investors
https://unctad.org/news/post-brexit-uk-exports-could-fall-32-billion-due-non-tariff-measures-and-tariffs
https://www.eia.gov/energyexplained/us-energy-facts/imports-and-exports.php
http://www.oliverwyman.com/content/dam/oliver-wyman/v2/publications/2018/march/Oliver-Wyman_Clifford-Chance-The-Red-Tape-Cost-of-Brexit.pdf