CORRIGENDUM 1 FOR RFP FLOATED ON GEM SUPPLY-INSTALLATION TESTING-COMMISSIONING-OPERATIONALISATION OF AIR COOLED DUCTED PACKAGED AIR CONDITIONERS; AMC CHARGES FOR 2ND, 3RD & 4TH YEAR ALONG WITH DISMANTLING AND BUYBACK OF EXISTING UNITS AT NATIONAL HOUSING BANK – MUMBAI REGIONAL OFFICE