1. Act from 10 April 1997. Energy Law. Journal of Laws No. 54, item 348. https://isap.sejm.gov.pl/isap.nsf/DocDetails.xsp?id=WDU19970540348 (in Polish).
2. Act from 13 July 2023. Act on facilitating the preparation and implementation of investments in agricultural biogas plants. Journal of Laws 2023, item 1597. https://isap.sejm.gov.pl/isap.nsf/DocDetails.xsp?id=WDU20230001597 (in Polish).
3. Act from 14 March 2014. Act amending the Energy Law and certain other acts. Journal of Laws 2014, item 490. https://isap.sejm.gov.pl/isap.nsf/DocDetails.xsp?id=WDU20140000490 (in Polish).
4. Act from 17 August 2023. Act amending the Act on renewable energy sources and certain other acts. Journal of Laws 2023, item 1762. https://isap.sejm.gov.pl/isap.nsf/DocDetails.xsp?id=WDU20230001762 (in Polish).
5. Act from 20 February 2015. Act on renewables energy sources. Journal of Laws 2015, item 478. https://isap.sejm.gov.pl/isap.nsf/DocDetails.xsp?id=WDU20230001436 (in Polish).