| Authors(s) | Spoel, S. van der |
| Year | 1975b |
| Title | Preliminary note on variation of protoconchae of Clio pyramidata (Linnaeus, 1767) (Mollusca, Pteropoda). Bull. Zoöl. Mus. Univ. Amsterdam 4(21): 187-190, 2 tabs, 2 figs. |
| Authors(s) | Spoel, S. van der |
| Year | 1975b |
| Title | Preliminary note on variation of protoconchae of Clio pyramidata (Linnaeus, 1767) (Mollusca, Pteropoda). Bull. Zoöl. Mus. Univ. Amsterdam 4(21): 187-190, 2 tabs, 2 figs. |