1. Brachet, J.:Chemical embryology. Interscience Publishers, Inc., N. York, (1950), 1947.
2. Dean, A. C. R., Hinshelwood, C., Sir::Variations in the nucleic acid content of Bac. lactis aerogenes during the growth cycle. Proc. roy. Soc. London 151: 348, 1960.
3. Falcone, G., Nickerson, W. J.:Biochemistry of morphogenesis. Pergamon Press, London 1959.
4. Hase, E., Morimura, V., Mihara, S., Tamiya, H.:The role of sulphur in the cell division of Chlorella. Arch. Mikrobiol. 32: 87, 1958.
5. Hase, E., Otsuka, H., Mihara, S., Tamiya, H.:Role of sulphur in the cell division of Chlorella, studied by the technique of synchronous cultures. Biochim. biophys. Acta 35: 180, 1959a.