United Nations Framework Classification for Fossil Energy and Mineral Reserves and Resources 2009,
United Nations, 2010, VI, 20 с. : с табл., 978-92-1-117033-7.
.
United Nations Framework Classification for Fossil Energy and Mineral Reserves and Resources 2009.
Geneva: United Nations, 2010, VI, 20 с. : с табл., 978-92-1-117033-7.
(2010)
United Nations Framework Classification for Fossil Energy and Mineral Reserves and Resources 2009,
Geneva: United Nations, VI, 20 с. : с табл., 978-92-1-117033-7
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