“Evolutionary Perspectives on Energy Consumption of Raw Materials to Ensure Energy Production in the EU-2”. The Annals of “Dunarea de Jos” University of Galati. Fascicle IX, Metallurgy and Materials Science, vol. 37, no. 4, Dec. 2014, pp. 19-25, https://ojs.ugal.ro/index.php/mms/article/view/2221.