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Coal : bridge to the future | Bok | 662.66 W World coal study / - Cambridge, Mass. : Ballinger publishing company , 1980. - 247 s. (Report of the World Coal Study, WOCOL) - Språk: Engelsk | World coal study | 1980 |
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Future coal prospects : country and regional assessments | Bok | 662.66 W World coal study / - Cambridge, Mass. : Ballinger publishing company , 1980. - 577 s. (World Coal Study WOCOL) - Språk: Engelsk | World coal study | 1980 |