http://api.nbp.pl/

http://api.nbp.pl/api/exchangerates/tables/a/

http://api.nbp.pl/api/exchangerates/tables/a/?format=xml

http://api.nbp.pl/api/exchangerates/tables/a/?format=json

http://api.nbp.pl/api/exchangerates/tables/b/

http://api.nbp.pl/api/exchangerates/tables/a/2020-01-15/?format=xml

http://api.nbp.pl/api/exchangerates/tables/a/2020-01-15/?format=json
