- Brown, Lester, 1934-✖[entfernen]5
- Biodiversity.1
- Economic development1
- Emissions, Automobile1
- Environment1
- Kids for Saving Earth1
- Leopold, Aldo, 1886-19481
- Nelson, Gaylord, 1916-20051
- Population growth1
- Rainwater harvesting1
- Sombke, Laurence1
- Suzuki, David Takayoshi, 1936-1
- War1