I have offices at Konrad-Zuse-Zentrum and at TU Berlin. I spend the larger part of my time at ZIB, the larger part of my secretarial and scientific staff is also located at ZIB. If you want to reach me by phone, please try first my phone number at ZIB. If you want to send mail I suggest that you use the ZIB address.

Konrad-Zuse-Zentrum für Informationstechnik Berlin (ZIB) Takustraße 7 14195 Berlin Germany	TU Berlin Institut für Mathematik Sekretariat MA 3-1 (room MA 302) Straße des 17. Juni 136 10623 Berlin Germany	TU Berlin DFG Research Center Mathematics for key technologies Sekretariat MA 3-1 Straße des 17. Juni 136 10623 Berlin, Germany
Phone: +49/30/84185-210	Phone: +49/30/314-23266	Phone: +49/30/84185-110
Office: +49/30/84185-208   (Sylwia Markwardt) +49/30/84185-209   (Bettina Kasse)	Office: +49/30/314-28478 (Claudia Ewel) +49/30/314-23354 (Elke Pose)
Fax: +49/30/ 84185-269	Fax: +49/30/314-29260
groetschel@zib.de	groetsch@math.tu-berlin.de	Sprecher@FZT86.de