Efford, I. E., & Smith, B. M. (1972). Energy and the environment. Institute of Resource Ecology, University of British Columbia.
Cita Chicago (17th ed.)Efford, Ian E., i Barbara M. Smith. Energy and the Environment. Vancouver: Institute of Resource Ecology, University of British Columbia, 1972.
Cita MLA (9th ed.)Efford, Ian E., i Barbara M. Smith. Energy and the Environment. Institute of Resource Ecology, University of British Columbia, 1972.
Atenció: Aquestes cites poden no estar 100% correctes.