Population Dynamics in a Microfounded Predator-Prey Model, Discussion Paper No. 118-04, University of Siegen, 2004.

Aging in a Neoclassical Theory of Labor Demand, Discussion Paper No. 112-03, University of Siegen, 2003.

Economic Growth, a Golden Rule of Thumb, and Learning by Doing, Discussion Paper No. 95-01, University of Siegen, 2001.

Economic Growth, the Mathematical Pendulum, and a Golden Rule of Thumb, Discussion Paper No. 94-01, University of Siegen, 2001.

A Note on Public Goods: Non-Excludability Implies Joint Consumability, Discussion Paper No. 68-98, University of Siegen, 1998.