1. W. H. Blow,The Cainozoic Globigerinida, ed. E. J. Brill, part 1, pp. 1–221, Leiden, 1979.
2. R. A. Fisher, Dispersion on a sphere,R. Astr. Soc. Lond., A,217, 295–304, 1953.
3. M. Ibaraki, Geologic ages of “Lepidocyclina”, Miogypsina in Izu Peninsula as determined by planktonic foraminifera,J. Geol. Soc. Japan,87, 417–420, 1981 (in Japanese).
4. M. Ibaraki and R. Tsuchi, Planktonic foraminifera from Lepidocyclina horizon at Namegawa in the southern Izu Peninsula, central Japan,Rep. Fac. Sci. Shizuoka Univ.,>12, 115–127, 1978.
5. N. Ikebe and M. Chiji, Notes on top-datum of Lepidocyclina sensu lato in reference to planktonic foraminiferal datum,J. Geosci. Osaka City Univ.,14, 19–44, 1971.