If those fail, go to sourceforge.net/projects/jasperstudio/ and browse to /JaspersoftStudio/6.6.0/ manually.
JasperReports Library Archive on SourceForge Key Features of the 6.6.0 Release jaspersoft studio 660 download link
If those fail, go to sourceforge.net/projects/jasperstudio/ and browse to /JaspersoftStudio/6.6.0/ manually.
JasperReports Library Archive on SourceForge Key Features of the 6.6.0 Release