The gpsemantics readme file seems to be errant. * Implements Goldberg and O'Reilly's semantic Order and Majority * problems. See the README. I presume this file has information about what the problem is doing and which papers it references. Possibly these are the papers? [24] D. E. Goldberg and U.-M. O’Reilly, “Where Does the Good Stuff Go, and Why?,” in EuroGP 1998, W. Banzhaf, et al., Eds. Berlin: Springer-Verlag, 1998, pp. 16–36. [25] U.-M. O’Reilly and D. E. Goldberg, “How Fitness Structure Affects Subsolution Acquisition in Genetic Programming,” in GP ’98, J. R. Koza, et al., Eds. S -- ray