Gangtok, May 30 (PTI) The Special Intensive Revision (SIR) exercise commenced in Sikkim on Saturday, with booth level officers (BLOs) visiting households with enumeration forms, an official said. Chief Electoral Officer (CEO) Raj Kumar Yadav said the enumeration phase under the SIR of the electoral rolls commenced across Sikkim during the day and will continue till June 28. He said the BLOs are undertaking door-to-door visits to distribute enumeration forms. The electors are being urged to coope