| Bulletin of the National Science Museum Series C (Geology & Paleontology) | date of publication | 
          
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            | Bulletin of the National Science Museum Series C (Geology & Paleontology) Volume 18 Number 1 | March 1992 | 
          
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                |  | Kazumi YOKOYAMA, Tokiko TlBA, Kazuya CHIHARA: | P.1 | 
              
                |  | Picrite sill in the Sado Island, Japan |  | 
              
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                |  | Toshimasa TANAI: | P.13 | 
              
                |  | Juglandaceae from the Paleogene of Hokkaido, Japan |  |