Okadaira shell mound at Hitachi, being an appendix to Memoir vol. I, part I of the Science Department, Tokio Daigaku (University of Tokio)
Iijima, Isao, 1861-1921; Sasaki, Chujiro, b. 1857; Morse, Edward Sylvester, 1838-1925. Shell mounds of Omori