1. 1) Y. Nakamura, N. Ichizen, I. Kimura, H. Sugiyama and I. Okuda: Abstr. 8th Annu. Meeting Weed Sci. Soc. Japan, pp. 9–10, 1969 (in Japanese).
2. 2) I. Kimura, H. Sugiyama, N. Ichizen, Y. Yoshida and I. Okuda: Abstr. 4th Annu. Meeting Chemical Regulation of Plants Soc. Japan, pp. 51–52, 1969 (in Japanese).
3. 3) Y. Nakamura, K. Ishikawa and S. Kuwatsuka: Agric. Biol. Chem. 38, 1129–1135 (1974).
4. 4) Y. Nakamura, K. Ishikawa and S. Kuwatsuka: Abstr. 35th Annu. Meeting Weed Sci. Soc. Japan, p. 109, 1975 (in Japanese).
5. 5) Y. Nakamura, K. Ishikawa and S. Kuwatsuka: Agric. Biol. Chem. 41, 1613–1620 (1977).