in Proceedings of the 4th Summer School in Modern Mathematical Physics, MPHYS 2006
Pages: 275-282
Conference
4Th Summer School in Modern Mathematical Physics, Mphys 2006, Date: 3 September 2006 through 14 September 2006, Location: Belgrade, Sponsors: Ministry of Science and Environmental Protection;The Abdus Salam International Centre for Theoretical;Physics (ICTP);DFG Schwerpunkt String Theory;Ton Plus
