Tham khảo Julius_von_Sachs

  1. ↑ Farley, John. (1982). Gametes & Spores: Ideas about Sexual Reproduction, 1750-1914. Johns Hopkins University Press. p. 132
  2. ↑ Dennert, Eberhard. (1904). At the Deathbed of Darwinism: A Series of Papers. German Literary Board. p. 38
  3. ↑ Croizat, Léon. (1960). Principia Botanica: Or, Beginnings of Botany. Weldon & Wesley. p. 1680