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.
Burr, William. "Consultation is Presidential Business": Secret Understandings on the Use of Nuclear Weapons, 1950-1974. Electronic Briefing Book No. 159. Washington, D.C.: National Security Archive, 2005. https://nsarchive2.gwu.edu/NSAEBB/NSAEBB159/.
Butcher, Martin, Otfried Nassauer, Tanya Padberg, and Dan Plesch. Questions of Command and Control: NATO, Nuclear Sharing, and the NP. PENN Research Report 2000.1. Berlin: Project on European Nuclear Non-Proliferation, 2000. http://www.bits.de/public/pdf/00-1command.pdf.
Congressional Research Service. Authority to order the use of nuclear weapons (United States, United Kingdom, France, Soviet Union, People's Republic of China). Washington, DC: Congressional Research Service, 1975. https://catalog.hathitrust.org/Record/003216700/Home.