I was a visiting researcher at the following places:

• Data Analysis and Pattern Recognition Lab, University of Applied Sciences, Wolfenbuettel / Braunschweig, GERMANY, at the invitation of Prof. Frank Klawonn, Head of DAPAR.
 
• Dept of Mathematics and Descriptive Geometry, Slovak University of Technology, Bratislava, SLOVAKIA, at the invitation of Prof. Radko Mesiar, Head of DMADG.
 
• Dept. of Knowledge-Based Mathematical Systems, Johannes Kepler University, Linz, AUSTRIA, atthe invitation of Prof. E. P. Klement, Head of DKBMS.
 
• Institute for Research and Applications in Fuzzy Modeling, Univ. of Ostrava, CZECH REPUBLIC, at the invitation of Prof. Vilem Novak, Director, IRAFM.
 
• Institute of Mathematics, University of Silesia, Katowice, POLAND, at the invitation of Dr. Michal Baczynski.