Anonymous Animals is a series of graphic artwork by Osamu Sato. It may be viewed in a partially incomplete form on the defunct OSD website.
According to the defunct OSD website there was an exhibition for Anonymous Animals, held in November 1992 at the Tierrart Gallery in Tokyo. The postcard scan below, showcased on the same website, specifies it took place from November 4-21.
Partially Lost Status
At least one picture is believed to be missing from the above online gallery; a Japanese Twitter user has shown it's featured in an art textbook. It's unknown how many works are in the complete series.