
https://ec.europa.eu/research/evaluations/pdf/archive/other_reports_studies_and_documents/hlg_2017_report.pdf

http://letter_to_department_for_exiting_the_european_union_to_publish_the_findings_of_the_analysis_it_has_carried_out_of_the_impact_of_different_brexit_outcomes_for_the_uk_economy

https://theconversation.com/why-the-eus-singapore-ruling-does-not-lead-to-a-smoother-brexit-road-for-britain-78116