1. Ash, C. Trends Microbiol. 4, 371–372 (1996).
2. Fleming, A. Br. J. Exp. Pathol. 10, 226–236 (1929).
3. Cassell, G. et al. in Office of Technology Assessment, Congress of the United States. 1–31 (US Government Printing Office, OTA-H-629, Washington, DC, 1995).
4. Fernandes, P.B. & Chu, D.T.W. Annu. Rep. Med. Chem. 22, 117–126 (1987).
5. Andriole, V.T. Drugs 45 suppl 3, 1–7 (1993).