C.S Glantz, R.B. Bass, J.R. Casah, G.A. Coles, D.J. Gower, J.J. Heilman, M.D. Lammets, and J.L. Thomas, Pacific Northwest National Laboratory, NUREG/CR-6847, Cyber Security Self-Assessment Method for U.S. Nuclear Power Plants, October 2004. Unclassified.