1. On Purposeful Systems;Ackoff,1972
2. Individual Needs, Social Structures, and Indicators of National Development;Allardt,1973
3. “Virtue, Obligation and Politics” Revisited;Bank;Amer. Pol. Sci. Rev.,1976
4. Political Action;Barnes,1979
5. Toward a Facet Theory of a Sequential Order of Societal Needs;Ben-Sira;Quality and Quantity,1979