Venezky, D.Y., and Snedigar, Seth, 2006, A new system for publishing and archiving volcano hazard information statements using the Common Alerting Protocol (CAP) [abs.]: in Geoinformatics 2006 abstracts, Brady, S.R., Sinha, R.K., and Gundersen, L.C., eds., U.S. Geological Survey Scientific Investigations Report 2006-5201, p. 11, available at http://pubs.usgs.gov/sir/2006/5201/ .
link to USGS page, containing links to the PDF on a USGS server