Appunn, Kerstine (7. 8. 2018). „Germany's three lignite mining regions”. The Clean Energy Wire. Архивирано из оригинала 26. 11. 2018. г. Приступљено 5. 7. 2019. „Germany has been the largest lignite producer in the world since the beginning of industrial lignite mining. It still is, followed by China, Russia, and the United States. The softer and moister lignite (also called brown or soft coal) has a lower calorific value than hard coal and can only be mined in opencast operations. When burned, it is more CO2 intensive than hard coal.”
Appunn, Kerstine (7. 8. 2018). „Germany's three lignite mining regions”. The Clean Energy Wire. Архивирано из оригинала 26. 11. 2018. г. Приступљено 5. 7. 2019. „Germany has been the largest lignite producer in the world since the beginning of industrial lignite mining. It still is, followed by China, Russia, and the United States. The softer and moister lignite (also called brown or soft coal) has a lower calorific value than hard coal and can only be mined in opencast operations. When burned, it is more CO2 intensive than hard coal.”