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| JOHANSEN BAD OG RØRSERVICE AS | 990718245 | OSLO |
| JOHANSEN VVS AS | 979212445 | OSLO |
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| JØRGENSEN AS | 930827142 | OSLO |
| JOSTEIN RØNSEN ARKITEKTER AS | 975795942 | OSLO |
| JR ANLEGG AS | 934763505 | OSLO |
| JSG RØR AS | 923171401 | OSLO |
| JUULS RØRSERVICE AS AUT RØRLEGGERFIRMA | 943919607 | OSLO |
| J&V SNEKKERE AS | 915244882 | OSLO |
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| KAARUD AS | 913068920 | OSLO |
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| KJ PROSJEKT AS | 926613170 | OSLO |
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| KLIMASERVICE OSLO AS | 915440622 | OSLO |
| KNEM OG NÆSVIK AS | 982409829 | OSLO |
| KNUT LIE AS | 919396377 | OSLO |
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