1. Decision methods in the theory of ordinals;Büchi, J. Richard;Bull. Amer. Math. Soc.,1965
2. J. R. Buchi, C. E. Elgot and J. B. Wright, The nonextstence of certain algorithms of finite automata theory, Notices Amer. Math. Soc. 5 (1958), 98.
3. Weak second-order arithmetic and finite automata;Büchi, J. Richard;Z. Math. Logik Grundlagen Math.,1960
4. On a decision method in restricted second order arithmetic;Büchi, J. Richard,1962
5. A. Church, Application of recursive arithmetic to the problem of circuit synthesis, Summaries of Talks Presented at the Summer Institute for Symbolic Logic, Cornell Univ. 1957, 2nd ed; Princeton, N. J., 1960, 3-50.