Penner, S. S. (1982). New sources of oil & gas: Gases from coal, liquid fuels from coal, shale, tar sands, and heavy oil sources (First edition.). Pergamon. https://doi.org/10.1016/C2013-0-06056-2
Lua i Stíl Chicago (17ú heag.)Penner, S. S. New Sources of Oil & Gas: Gases from Coal, Liquid Fuels from Coal, Shale, Tar Sands, and Heavy Oil Sources. First edition. Oxford, New York: Pergamon, 1982. https://doi.org/10.1016/C2013-0-06056-2.
Lua MLA (9ú heag.)Penner, S. S. New Sources of Oil & Gas: Gases from Coal, Liquid Fuels from Coal, Shale, Tar Sands, and Heavy Oil Sources. First edition. Pergamon, 1982. https://doi.org/10.1016/C2013-0-06056-2.
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