1. Duchesneau, F. Genèse de la Théorie Cellulaire (Bellarmin, Paris, Montreal, 1987).
2. Harris, H. The Birth of the Cell (Yale Univ. Press, New Haven, 1999).
3. Haeckel, E. Generelle Morphologie der Organismen (G. Reimer, Berlin, 1866).
4. Rinard, R. The problem of the organic individual: Ernst Haeckel and the development of the bigenetic law. J. Hist. Biol. 14, 249–275 (1981).
5. Nyhart, L. K. Biology Takes Form: Animal Morphology and the German Universities, 1800–1900 (Univ. Chicago Press, Chicago, 1995).