"Sigma" can refer to;
These are photos from concerts where Sigma played, so they may be of other bands that played the concert as well.
Guilfest 2014 Jul 18 - 20, 2014 Guildford, England, United Kingdom Uploaded by Craig Hatfield
Glastonbury Festival Jun 29, 2014 Pilton, England, United Kingdom Uploaded by Martin Scarborough
Heaven 17
Guilfest 2012 Jul 13 - 15, 2012 Guildford, England, United Kingdom Uploaded by Craig Hatfield
Björn Again
Nouvelle Vague
Jimmy Cliff
Mr B the Gentleman Rhymer
Tim Minchin
Buzzcocks
