
https://www.gov.pl/web/primeminister/letter-from-prime-minister-mateusz-morawiecki-to-the-heads-of-governments-and-the-presidents-of-the-european-council-the-european-commission-and-the-european-parliament-on-relations-between-national-law-and-european-law

http://www.msz.gov.pl/en/news/deputy_minister_renata_szczech_takes_part_in_a_debate_on_europe_s_future

http://eur-lex.europa.eu/legal-content/EN/TXT/PDF/?uri=CELEX:52016DC0950&from=en