10/2008-03/2009: Department of Mathematics, Technical University of Kaiserslautern (TU-KL), Germany
(upon invitation by Professor Ralf Korn)
02/2007-09/2007: Department of Mathematics, Technical University of Kaiserslautern (TU-KL), and the Fraunhofer ITWM, Germany
(upon invitation by Professor Ralf Korn in connection with DAAD)
08/2005-09/2005: Department of Numerical Methods in Mechanical Engineering, Darmstadt University of Technology, Germany (upon invitation by Professor Michael Schaefer)
06/2005-08/2005: Department of Mathematics, Technical University of Kaiserslautern (TU-KL), and the Fraunhofer ITWM, Germany
(upon invitation by Professor Ralf Korn)
08/2004-09/2004: Department of Numerical Methods in Mechanical Engineering, Darmstadt University of Technology, Germany
(upon invitation by Professor Michael Schaefer)