1. Institut für Angewandte Mathematik, Universität Bonn, Wegelerstr. 6, D-53115 Bonn, Germany
2. SFB 256, Bonn, BiBoS, Bielefeld - Bonn, Germany
3. CERFIM, Locarno and USI, Switzerland
4. St. Petersburg State University for Architecture and Civil Engineering, 2-ja Krasnoarmejskaja 4, 198005, St. Petersburg, Russia
5. UkrNIIRESURS, Bozenko 84, Kiev GSP 03680, Ukraine