Efford, I. E., & Smith, B. M. (1972). Energy and the environment. Institute of Resource Ecology, University of British Columbia.
Chicago-čujuhus (17. p.)Efford, Ian E., juo Barbara M. Smith. Energy and the Environment. Vancouver: Institute of Resource Ecology, University of British Columbia, 1972.
MLA-čujuhus (9. p.)Efford, Ian E., juo Barbara M. Smith. Energy and the Environment. Institute of Resource Ecology, University of British Columbia, 1972.
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