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2. Sequence stratigraphy and coal petrography applied to the Candiota coal field, Rio Grande do Sul, Brazil: a depositional model;Alves;International Journal of Coal Geology,1996
3. Standard classification of coals by rank (D388-95);American Society for Testing and Materials (ASTM),1996
4. Standard test methods for collection of a gross sample of coal (D2234-89);American Society for Testing and Materials (ASTM),1996
5. Standard practice for proximate analysis of coal and coke (D3172-89);American Society for Testing and Materials (ASTM),1996