https://www.piie.com/sites/default/files/documents/wp22-12.pdf
https://www.politico.eu/wp-content/uploads/2020/05/LetterVDL12052020EN.pdf
https://ecipe.org/blog/trade-relationship-status-open/?mc_cid=88a1251206&mc_eid=286ad5ef5f
https://www.ipg-journal.de/regionen/asien/artikel/deal-der-superlative-4816/