1. Universal physiology;Boulding;Contemporary Sociology,1979
2. The noncybernetic nature of ecosystems;Engelberg;The American Naturalist,1979
3. Industrial dynamics;Forrester,1961
4. Principles of systems. Pages numbered variously;Forrester,1968
5. Ecosystem succession: a general hypothesis and a test model of a grassland;Gutierrez,1980