"Sofre" . . "TECHNOLOGY & ENGINEERING / Chemical & Biochemical" . . "Combustió" . . "Carbó" . . "Kohle." . . "IEA Coal Research (London)" . . "Entschwefelung." . . "International Energy Agency Coal Research, London." . . . . "Electronic books"@en . . . "The PROBLEMS of Sulphur" . . . "The Problems of sulphur / IEA Coal Research, London" . . . . . . "The problems of sulphur" . . . . . . . . "The Problems of sulphur" . "The Problems of sulphur"@en . . . . . . .