1. QRAS 1.7 User's manual. University of Maryland, College Park, Maryland, USA; 2002.
2. Smith C, O'Connor B. Probabilistic risk assessment for the international space station PRA. In: Proceedings of the ESREL 2001, Torino, Italy; September 16–20, 2001.
3. Probabilistic risk assessment—procedures guide for NASA managers and practitioners—version 1.1. Prepared for office of safety and mission assurance, NASA Headquarters, Washington, DC 20546; August 2002, http://www.hq.nasa.gov/office/codeq/doctree/praguide.pdf.
4. PRA procedures guide, NUREG/CR 2300, US NRC, Washington DC; 1983.
5. Fault tree handbook, NUREG-0492;Vesely,1981