Concept selection of normally unmanned installations in the North Sea: A risk based model for concept selection of normally unmanned installations in the North Sea Fross, Richard Lunds tekniska högskola (LTH) 2012 Öppna dokument
Railroad accident report : collision involving three consolidated rail corporation freight trains operating in fog on a double main track near Bryan, Ohio, January 17, 1999 National Transportation Safety Board (NTSB) 2001 Öppna dokument