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Yeats, Robert S. (June 1, 1999). "Forecasting the 1989 Loma Prieta Earthquake—Close But No Cigar". Living with Earthquakes in the Pacific Northwest. Vol. 36, issue 10. p. 5.7.11.1. doi:10.5860/choice.36-5709. S2CID128171993.
Charles, Elizabeth C.; Rasmussen, Kathleen B., eds. (2020). "Reagan-Gorbachev Meetings in Geneva, November 1985: Memorandum of Conversations". Foreign Relations of the United States: Soviet Union, March 1985 to October 1986(PDF) (Report). Vol. 5. Washington, D.C.: Department of State. pp. 650-720 (print) pp. 681-751 (pdf).
Reagan, Ronald; Shultz, George P. (2003). Skinner, Kiron K.; Graebner Anderson, Annelise; Anderson, Martin (eds.). Reagan: A Life In Letters. New York: Free Press. p. 288. ISBN9780743219662. OCLC52493559.