1. Nakagawa, Y., Ugeo, S., and Vajima, H., Chemy. Ind., 42, 1238–1243 (1956).
2. Amico, A., Bruno, S., and Papa, F., Flora salutaris, 5, 1–7 (1967).
3. De Leo, P., Dalessandro, G., De Santis, A., and Arrigoni, O., Pl. Cell Physiol., 14, 481–486 (1973).
4. De Leo, P., Dalessandro, G., De Santis, A., and Arrigoni, O., Pl. Cell Physiol., 14, 487–496 (1973).
5. Liso, R., and Calabrese, G., Phycologia, 14, 1–4 (1975).