1. D. G. Davies and J. W. Costerton, Center for Biofilm Engineering, Montana State University, Bozeman, MT 59717–3980, USA.
2. M. R. Parsek and E. P. Greenberg, Department of Microbiology, University of Iowa, Iowa City, IA 52242, USA.
3. J. P. Pearson and B. H. Iglewski, Department of Microbiology and Immunology, University of Rochester, Rochester, NY 14642, USA.