The resources below are books, articles, and other media that are useful references for aspects of this topic. When they are complete, each reference will be described and tagged. See here for an example of a more or less complete entry.
Hoffman, David E. "The Russian Nuclear Button: New questions about the Soviet legacy of three briefcases." Foreign Policy. May 27, 2010. https://foreignpolicy.com/2010/05/27/the-russian-nuclear-button-2/.
Podvig, Pavel. "Risks of Nuclear Command and Control Accidents." In Understanding Nuclear Risks, edited by John Borrie, Tim Caughley, and Wilfred Wan, 53-59. Geneva, Switzerland: United Nations Institute for Disarmament Research (UNIDIR), 2017. http://www.unidir.org/files/publications/pdfs/understanding-nuclear-weapon-risks-en-676.pdf.