Contact the Swedish Transport Agency (Transportstyrelsen).
Contact the Swedish National Road and Transport Research Institute (VTI) or the Swedish Transport Administration (Trafikverket). Information is also available at Transguide.
As a general rule, SHK investigates road traffic occurrences only when commercial or public transport vehicles are involved.
The database does not go as far back as that. You can, however, find the report on the SHK web site under Civil Aviation.
SHK used to be able to delegate glider accident investigations to the a non-governmental national glider association. Those reports can be found at Airsport Sweden.
The investigation was conducted by Poland. SHK has no translation in English. The Swedish Transport Agency has only a short summary in Swedish.
Contact the Norwegian Maritime Authority.
Look at the SHK web site under Civil Maritime Transport.
According to statutory rules SHK is required to complete an investigation, if possible, within
12 months from the day of the occurrence. That is, however, not always possible.
Swedish Accident Investigation Authority (English), Schwedische Ständige Untersuchungskommission für Grossunfälle (German), Commission suédoise d'enquête sur les accidents (French), Comisión Sueca de Investigación de Accidentes (Spanish), Ruotsin onnettomuuksientutkintatoimikunta (Finnish), Шведская государственная комиссия по расследованию аварийных ситуаций (Russian).