1. Allen, B. M.: The Embryonic development of the ovary and testis of the Mammals. Amer. Journ. Anat.,Vol. 3, 1904.
2. Derselbe Allen, B. M.: The origin of the sex-cells of Chrysemis. Anat. Anz., Bd. 29, 1906.
3. Derselbe Allen, B. M.: An important Period in the history of the sex-cells of Rana pipiens. Anat. Anz., Bd. 31, 1907.
4. Derselbe Allen, B. M.: The origin of the sex-cells of Amia and Lepidosteus. Anat. Rec., Vol. 3, 1909.
5. Amma, K.: Über die Differenzierung der Keimbahnzellen bei den Copepoden. Arch. f. Zellforschung, Bd. 6, 1911.