1. Herb Enderton, Elements of recursion theory, in: J. Barwise, ed.,Handbook of Mathematical Logic (North-Holland, Amsterdam 1977)
2. Paul Erdös and George Mills, Some bounds for the Ramsey-Paris- Harrington numbers, to appear
3. Jussi Ketonen and Robert M. Solovay, Rapidly growing Ramsey functions, to appear
4. Martin H. Löb and Stan Wainer, Hierarchies of number-theoretic functions I, II, Archiv f. math. Logik 13 (1970), pp. 39–51, 97-113
5. Jeff Paris and Leo Harrington, A mathematical incompleteness in Peano arithmetic, in: J. Barwise, ed.,Handbook of Mathematical Logic (North-Holland, Amsterdam 1977)