APA

Peters W., Institute of Research and Projects for Oil and Gas, World Petroleum Congress (10th : 1979 sept. 9-14 : Bucharest) & Institute of Research and Projects for Oil and Gas.Coal as an oil or gas replacement. : .

Chicago

Peters W, Institute of Research and Projects for Oil and Gas, World Petroleum Congress (10th : 1979 sept. 9-14 : Bucharest) and Institute of Research and Projects for Oil and Gas.Coal as an oil or gas replacement. : .

Harvard

Peters W., Institute of Research and Projects for Oil and Gas, World Petroleum Congress (10th : 1979 sept. 9-14 : Bucharest) and Institute of Research and Projects for Oil and Gas.Coal as an oil or gas replacement. : .

MLA

Peters W, Institute of Research and Projects for Oil and Gas, World Petroleum Congress (10th : 1979 sept. 9-14 : Bucharest) and Institute of Research and Projects for Oil and Gas.: . .