swatch Home Page: http://www.stanford.edu/~atkins/swatch/
“Centralized System Monitoring with Swatch” by Stephen Hansen and Todd Atkins, creators of swatch. http://www.stanford.edu/~atkins/swatch/lisa93.html
“Watching Your Logs” by Lance Spitzner. A brief introduction to swatch. http://www.enteract.com/~lspitz/swatch.html
Mastering Regular Expressions by Jeffrey E. F. Friedl (O'Reilly & Associates, 1998)