1. Nelligan, I. and Calam, C.T. (1980). Biotech. Lett.,2, 531.
2. Calam, C.T. and Ismail, B. A-K. (1980). J. Chem. Tech Biotechnol.30, 249.
3. Mou, D-G. (1979). Thesis, Massachusetts Inst. Technol., Cambridge, Mass. USA.
4. Calam, C.T. FEMS Symp, Aug 1981, ?Overproduction of Secondary Metabolic Products?, Academic Press, London, 1982, p.89.
5. Wang, H.Y., Cooney, C.L. and Wang, D.I.C. (1979). Biotech. Biotechnol.21, 975.