1. UNIV. of OULU, Lab. of Chemical Process Engineering, Linnanmaa, FIN-90570 Oulu, Finland
2. EPFL, DGR-IGE-Biotechnologie Environnementale, CH-B Ecublens, 1015 Lausanne, Switzerland
3. Technical University of Denmark, Dept. of Env.Sci. and Eng., Building 115, DK-2800, Lyngby, Denmark
4. University College, Earlsfort Terrace, Dublin 2, Ireland
5. EAWAG, Eng. Science Dep., Ueberlandstr. 133, CH-8600 Duebendorf, Switzerland