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2. Watanabe, A., paper read at the tenth general meeting of the Bot. Soc. of Japan (Tokyo, 1942).
3. Watanabe, A., Miscellaneous Reports of Research Inst. for Nat. Resources (Tokyo), Nos. 17–18, 61 (1950) (in Japanese).
4. Nishigaki, S., paper read at the twenty-first general meeting of the Society of Soil and Manure, Japan (1950).
5. Konishi, C., paper read at the twenty-second general meeting of the Society of Soil and Manure, Japan (1951).