في 24 آذار علماء البراكين في USGS - ومن بينهم جونستون - أصبحوا أكثر ثقة بأن النشاط الزلازالي كان إشارة بثورة وشيكة للبركان* David A. Johnston (متحف الولايات المتحدة الأمريكية للجيلوجية)* David Alexander Johnston – memoriam article by Wes Hildreth – includes 1978 photograph of Johnston (USGS Geological Survey Circular 838, hosted by the US National Park Service)* David Johnston – memorial page that includes photographs of Johnston following his arrival at the volcano (St. Helens Hero website)* This is it – 1995 local newspaper retrospective on Johnston (St. Helens Hero website)* The Victims of the Eruption – memorial page that includes a photograph of the Hoffstadt Bluffs memorial plaque (The many faces of Mount St. Helens website)* Mount St. Helens - Victims – map that shows the position of Johnston and the others killed by the eruption (The Daily News, TDN.com)
== Major publications ==== References ===== Bibliography =====External links==*David A. Johnston (United States Geological Survey obituary, hosted by the Cascades Volcano Observatory)*David Alexander Johnston – memoriam article by Wes Hildreth – includes 1978 photograph of Johnston (USGS Geological Survey Circular 838, hosted by the US National Park Service)*David Johnston – memorial page that includes photographs of Johnston following his arrival at the volcano (St. Helens Hero website)*This is it – 1995 local newspaper retrospective on Johnston (St. Helens Hero website)*The Victims of the Eruption – memorial page that includes a photograph of the Hoffstadt Bluffs memorial plaque (The many faces of Mount St. Helens website)*Mount St. Helens - Victims – map that shows the position of Johnston and the others killed by the eruption (The Daily News, TDN.com)