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Lignite - Wikipedia
Lignite | Uses, Formation, Properties | Britannica
Lignite Definition & Meaning - Merriam-Webster
Lignite - Energy Education
The end of the world's capital of brown coal - BBC
Coal explained - U.S. Energy Information Administration (EIA)
What Is Lignite? | Lignite Energy Council
Lignite Coal, Kentucky Geological Survey, University of Kentucky
What is Lignite? - ThoughtCo
Lignite - Simple English Wikipedia, the free encyclopedia