The Dynamics of Tephra Fall - a brief description of how and why tephra falls occur.
The Rise and Dispersion of Tephra Plumes - a link to a web page showing different types of dispersion patterns for tephra plumes.
Tephra Hazards - a general description of the hazards produced from the fall of tephra.
Tephra Catalog of the World - a catalog showing the magnitude and time of deposition for various tephra deposits throughout the world.
Tephra Magazine - a New Zealand magazine that discusses volcanoes and their hazards.
Tephrabase - a database developed at the University of Edinburgh of tephra deposits and their source volcanoes.

Tephrabase Web Pages http://www.geo.ed.ac.uk/tephra/tbasehom.html
Tephra Magazine Web Pages http://inform.dia.govt.nz:8080/mocd/tephra/tephraindex.html
Michigan Technological University Web Pages, Including:
Volcanoes, Atmosphere and Climate
http://bigmac.civil.mtu.edu/home/classes/ce459/public/p14/home.html
Volcanoes Pages http://www.geo.mtu.edu/volcanoes/
Volc Web Pages http://www-rk.edu.kagoshima-u.ac.jp/sci/volc/index_e.html