Works
• Cytotaxonomic Studies of Compositae 3: On the Species Problems in Japanese Cacalia Hastata and Its Allies by Hiroshige Koyama - 1968 • On Cacalia Yatabei and Its Related Species by Hiroshige Koyama - 1968 • Taxonomic studies on the tribe Senecioneae of Eastern Asia by Hiroshige Koyama - 1969 • Phytogeography of Some Flowering Plants of the Tsushima Islands by Hiroshige Koyama - 1970 • Blumea Conspicua, as a Species Endemic to the Ryukyu Islands by Hiroshige Koyama - 1974 • Notes on some species of Chinese Cacalia 3 by Hiroshige Koyama - 1979 • Natural history researches of the Abukuma mountains and Its Adjacent Regions by Hiroshige Koyama, Hiroshige Koyama - 1995 • Flora and Fauna of the Imperial Palace, Tokyo by Hiroshige Koyama - 2000 == References ==