Normal forms for derivations in Arai's \(\text{AI}_\xi^-\)
In a previous paper [Tsukuba J. Math. 21, 285-304 (1997; Zbl 0895.03024)], the author extended a normalization theorem due to the reviewer [Ann. Pure Appl. Log. 62, 65-79 (1993; Zbl 0786.03040)] to obtain a statement implying \(\omega\)-consistency of first-order arithmetic PA. Now he extends statements and proofs to theories of \(\xi\) times iterated inductive definitions.
scientific article; zbMATH DE number 1247879