A megalospheric schizont of Nummulites perforatus (MONTFORT) from upper Lutetian of the Yusan Formation, Haha-Jima (Hillsborough Island), Ogasawara Islands, Japan
K. Matsumaru, A megalospheric schizont of Nummulites perforatus (MONTFORT) from upper Lutetian of the Yusan Formation, Haha-Jima (Hillsborough Island), Ogasawara Islands, Japan, Revue de micropaleontologie , 37(2), 1994, pp. 161-165