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3. Biochemical factors in coal formation;Flaig,1972
4. The comparative study of the Okefenokee Swamp and the Everglades-mangrove swamp-marsh complex of southern Florida;Spackman,1974
5. The distribution of sulfur and organic matter in various fractions of peat: Origins of sulfur in coal;Casagrande;Geochim. Cosmochim. Acta,1980