| 1)  | 
            Musée des arts et métiers - LE
            WEB; 
            Foucault's pendulum at the Pantheon;  
            http://www.cnam.fr/museum/foucault/fouc_index/foucault_ca.html
             | 
        
        
            | 2)  | 
            Nan'niti,T., H.Akamatsu, T.Nakai,
            K.Fujii (1964) An Observation of a Deep Current in
            the Southern East Sea of Tori Shima, The
            Oceanographical Magazine, vol. 15, 113-122.  | 
        
        
            | 3)  | 
            Nan'niti,T., H.Akamatsu, T.Nakai
            (1964) Further observation of a deep current in the
            east-north-east sea of Torishima. The Oceanographical
            Magazine, vol. 16, 11-19.  | 
        
        
            | 4)  | 
            Ootsuka,M. (1980) Measuring the
            Earth (in Japanese), Asahi Shinbun-Sha  |