1. Why do we recycle;Ackerman,1997
2. Mixed signals: market incentives, recycling, and the price spike of 1995;Ackerman;Resources, Conservation and Recycling,2002
3. Ambivalent Joint Production and the Natural Environment. An Economic and Thermodynamic Analysis;Baumgärtner,2000
4. Baumgärtner, S., 2002. Ambivalence of secondary resources: joint production, limits to substitution and costly disposal. Revised version of: Ambivalence of joint outputs and the trade-off between disposal and productive use. Discussion Paper No. 311, Department of Economics, University of Heidelberg.
5. Analyse der Kostenstruktur der kommunalen Abfallentsorgung;Behrens,1997