Metaxas Α., Georgakopoulos Α.Ν., Karageorgiou D.Μ.Μ., G. Papanikolaou, and E.D. Karageorgiou. 2010. “CO2 CONTENT OF GREEK LIGNITE: THE CASE OF PROASTIO LIGNITE DEPOSIT IN PTOLEMAIS BASIN, NORTHERN GREECE”. Bulletin of the Geological Society of Greece 43 (5):2274-83. https://doi.org/10.12681/bgsg.11427.