1. Div. of Meteorol., NIAS; Crop production and unusual weather 1976. in Japanese
2. Div. of Statis. and Infor., Minist. of Agric. Forest. and Fishery. Crop Statistics (annual). in Japanese
3. Div. of Statis. and Infor., Minist. of Agric. Forest. and Fishery. Pocket Statistics of Agriculture (annual). in Japanese
4. Fedorov, E.K.: Weather and Yield. Hydrometeorological Printing Office, Leningrad, pp. 56 (1973) in Russian
5. Folland, C.K.: Recent work on some-quasi-cyclic fluctuations of meteorological parameters British climate. Weather, 32, 336–342 (1977)