Não informado. (1921). Contribution from the Institute of Geology and Paleontology. Tohoku University.
Παραπομπή σε μορφή Chicago (17η εκδ.)Não informado. Contribution from the Institute of Geology and Paleontology. Sendai, Japão: Tohoku University, 1921.
Παραπομπή σε μορφή MLA (8th εκδ.)Não informado. Contribution from the Institute of Geology and Paleontology. Tohoku University, 1921.
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