Harpoceras ikianum Yokoyama
| 1964. | Harpoceras ikianum Yokoyama Holotype Shikama, T. 1964 p. 154, pl. 54, fig. 3a,b |
| 1952. | Harpoceras ikianum Yokoyama Holotype Shikama, T. 1952 p. 116, pl. 20, fig. 11a,b |
| 1943. | Harpoceras ikianum Yokoyama Holotype Shikama, T. 1943 p. 184, pl. 20, fig. 11a,b |
| 1904. | Harpoceras Ikianum Yokoyama Holotype Yokoyama, M. 1904a p. 5, pl. 1, fig. 5a, b |
| Condition: | Present |
| Taxonomy: | Mollusca: Cephalopoda: |
| Geologic Time: | Mesozoic: |
| Shikama, T., 1943: A handbook of illustrated fossils from Japanese and their adjacent territories., pp. 1–279, pls. 1–46. Nippon Koubutu Syumi-no-kai, Kyoto. (in Japanese) (Reference No. 0616) |
| Shikama, T., 1952: A handbook of illustrated fossils from Japanese and their adjacent territories., pp. 1–376, pls. 1–57. Nippon Koubutu Syumi-no-kai, Kyoto. (in Japanese) (Reference No. 0617) |
| Shikama, T., 1964a: Index fossils of Japan., pp. 1–287, pls. 1–80. Asakura Shoten, Tokyo. (in Japanese) (Reference No. 0618) |
| Yokoyama, M., 1904a: On some Jurassic fossils from Rikuzen. Journal of the College of Science, Imperial University of Tokyo, vol. 18, art. 6, pp. 1–13, pls. 1–2. (Reference No. 0330) |
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| Ichikawa, T., 1988, no. 15, p. 166. |
| Ichikawa, T., 1988, no. 15, p. 152. |
| Ichikawa, T., 1988, no. 15, p. 142. |
| Ichikawa, T. and Hayami, I., 1978, no. 2, p. 299. |
