https://borderlex.net/2021/04/13/comment-quo-vadis-energy-charter-treaty/
https://www.politico.eu/article/diplomacy-disrupted-foreign-policy-improvised/?utm_source=POLITICO.EU&utm_campaign=1bd7d5bd60-EMAIL_CAMPAIGN_2019_11_22_11_14&utm_medium=email&utm_term=0_10959edeb5-1bd7d5bd60-190380769
https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/868378/200227_UK_trade_in_Numbers_full_web_version_final.pdf
https://cdn.ceps.eu/wp-content/uploads/2023/09/2023_17_Potential-Impact-of-Ukrainian-Accession-on-the-EUs-Budget.pdf