Gloomy Van Gogh self-portrait in Oslo gallery confirmed authentic

Only known painting by Dutch master while he had psychosis is 'unmistakably' his work

After decades of doubt, a gloomy self-portrait has been authenticated as a genuine work by Vincent van Gogh and the only known work painted while he had psychosis.

Self-Portrait (1889) has been in Norway's national collection since 1910 but its authenticity has been openly questioned since 1970. On Monday, the Van Gogh Museum in Amsterdam announced it was "unmistakably" a work by the artist.