1. Davis, Martin, “Unsolvable Problems,” in Jon Barwise, ed., Handbook of Mathematical Logic, North-Holland 1977, pp. 567–594.
2. Davis, Martin, Yuri Matijasevic, and Julia Robinson, “Hilbert’s Tenth Problem: Diophantine Equations: Positive Aspects of a Negative Solution,” Proceedings of Symposia in Pure Mathematics, vol.28(1976), pp. 323–378; Reprinted in Feferman, Solomon, ed. The Collected Works of Julia Robinson, Amer. Math. Soc. 1996, pp.269–378.
3. Friedman, Harvey, “Finite Functions and the Necessary Use of Large Cardinals,” Annals of Math., vol. 148(1998), pp. 803–893.
4. Friedman, Harvey, “Mathematically Natural Concrete Incompleteness,”
https://u.osu.edu/friedman.8/files/2014/01/Putnam062115pdf-15ku867.pdf
. To appear in a volume devoted to Hilary Putnam in the series: Outstanding Contributions to Logic, Sven Ove Hansson, editor-in-chief.
5. Gödel, Kurt, “The Present Situation in the Foundations of Mathematics,” in Solomon Feferman, et al, eds., Collected Works, vol. III, Oxford 1995, pp. 45–53.