1. Parekh S (2000) Strain improvement. In: J Lederberg (ed): Encyclopedia of microbiology, vol. 4, 2nd ed. Academic Press, San Diego, 428–443
2. Vinci VA, Byng G (1999) Strain improvement by nonrecombinant methods. In: AL Demain, JE Davies (eds): Manual of industrial microbiology and biotechnology, 2nd ed. ASM Press, Washington, DC, 103–113
3. Parekh S, Vinci VA, Strobel RJ (2000) Improvement of microbial strains and fermentation processes. Appl Microbiol Biotechnol 54: 287–301
4. Simpson IN, Caten CE (1979) Induced quantitative variation for penicillin titre in clonal populations of Aspergillus nidulans. J Gen Microbiol 110: 1–12
5. Baltz RH (1986) Mutagenesis in Streptomyces. In: AL Demain, NA Solomon (eds): Manual of industrial microbiology and biotechnology. ASM, Washington, DC, 184–190