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Energy consumption and optimum population
Landsberg, Hans H., (1971)
Health servies and an optimum level of population : are we part of the solution or part of the problem?
Lee, Philip R., (1971)
Food supplies and the optimum level of population
Brown, Lester R., (1971)
Research and development, know why, know how, know good
DeLaet, Christian, (1985)
The pollution problem
Laet, Christian de, (1972)
Environment
Singer, S. Fred, (1971)