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The Monetary Transmission Mechanism. Democritus University, Greece, 21 October 2003.
Optimum Currency Areas: A Critique. Democritus University, Greece, 21 October 2004.
Non-Linear Dynamics and Chaos Theory. With Stratos Nikolakakis, University of Amsterdam. New York College, Greece, 22 December 2003.
Stochastic Shocks of the European and the Greek Economic Fluctuations. Nikolaos Georgikopoulos and Costas Leon. Centre of Planning and Economic Research, Greece, 28 March 2008.