Williams, C. (1988). Mount St. Helens National Volcanic Monument: A pocket guide for hikers, viewers, and skiers. Mountaineers.
Cita Chicago Style (17a ed.)Williams, Chuck. Mount St. Helens National Volcanic Monument: A Pocket Guide for Hikers, Viewers, and Skiers. Seattle: Mountaineers, 1988.
Cita MLA (8a ed.)Williams, Chuck. Mount St. Helens National Volcanic Monument: A Pocket Guide for Hikers, Viewers, and Skiers. Mountaineers, 1988.
Precaución: Estas citas no son 100% exactas.