Não informado. (1921). Contribution from the Institute of Geology and Paleontology. Tohoku University.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रNão informado. Contribution from the Institute of Geology and Paleontology. Sendai, Japão: Tohoku University, 1921.
एमएलए (8वां संस्करण) प्रशस्ति पत्रNão informado. Contribution from the Institute of Geology and Paleontology. Tohoku University, 1921.
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