1. National Renewable Energy Laboratory, Golden, CO 80401 USA.
2. Charles University, Prague, 110 00 Staré Město, Prague, Czech Republic.
3. Czech Academy of Sciences, Institute of Mathematics, 110 00 Nové Město, Prague, Czech Republic.
4. Lehigh University, Bethlehem, PA 18015 USA.
5. Pacific Northwest National Laboratory, Richland, WA 99354 USA.