Coombs, M.L., Neal, C.A., Wessels, R.L., and McGimsey, R.G., 2006, Geothermal disruption of summit glaciers at Mount Spurr Volcano, 2004-6: an unusual manifestation of volcanic unrest: U.S. Geological Survey Professional Paper 1732-B, 33 p., available at http://pubs.usgs.gov/pp/pp1732/pp1732b/index.html .
website with link to full-text PDF