No information is available about this artist who was a member of Tadashige Ono's (1909-1990) Han no kai 版の会 (Print Society) formed in 1960 to nurture younger artists.1 The Society continued throughout Tadashige's lifetime and, perhaps, beyond.
Koga worked in a straight forward representational style with many of his/her works being printed in black and black gradations.
1 Tadashige's Han no kai should not be confused with Takei Takeo's Han no kai ("Hazlenut" Society) formed around 1935.
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