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| ABO OPPMÅLING AS | 897978032 | ASKER |
| ABO PLAN & ARKITEKTUR AS | 879951542 | BJØRNAFJORDEN |
| ABO PLAN & ARKITEKTUR STORD AS | 917495637 | STORD |
| ABORA PROSJEKT AS | 982753589 | BERGEN |
| ABOT AS | 915331262 | TØNSBERG |
| ABP ELEKTRO AS | 998583470 | ARENDAL |
| ABRAHAMSEN TORE | 970046666 | KRAGERØ |
| ABRAHAMSSON & HAUGSTVEDT AS | 983543847 | DRAMMEN |
| A. BRATVOLD | 923061754 | HAMAR |
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| ABSOLUTT RØRSERVICE Terje Vidar Rød | 883846532 | OSLO |
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| AD ARKITEKTER AS | 894404302 | LIER |
| ADD ARKITEKTER AS | 979497997 | OSLO |
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| ADITUS AS | 923383433 | DRAMMEN |
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