Hydrothermal eruption in Yellowstone National Park sends sightseers fleeing  The Guardian’Spectacular and definitely hazardous’: Yellowstone geyser erupts, firing steam and debris over nearby tourists  Livescience.comHydrothermal Explosion at Yellowstone Sends Tourists Racing for Safety  The New York TimesYellowstone Park Officials Conclude Cause Of Explosion  The Weather ChannelExplosion at Yellowstone National Park forces tourists to run for safety  Sky News