Basic Proof Theory (Cambridge Tracts in Theoretical Computer Science, 43)
A. S. Troelstra, H. Schwichtenberg, Cambridge Univ Pr (Txp)

The Higher Infinite: Large Cardinals in Set Theory from Their Beginnings (Springer Monographs in Mathematics)
Akihiro Kanamori, Springer-Verlag

A Course in Model Theory: An Introduction to Contemporary Mathematical Logic (Universitext)
Bruno Poizat, Moses Klein, Springer-Verlag

From Frege to Godel: A Source Book in Mathematical Logic, 1879-1931 (Source Books in History of Sciences)
Jean Van Heijenoort, Harvard Univ Press

Proof Theory and Logical Complexity (Studies in Proof Theory, Vol 1)
Jean-Yves Girard, Humanities Press

Introduction to Mathematical Logic and Type Theory (Computer Science & Applied Mathematics S.)
P. Andrews, Academic Press

Axiomatic Set Theory
Patrick Colonel Suppes, Dover Pubns

Non-well-founded Sets (Center for the Study of Language and Information Publication Lecture Notes)
Peter Aczel, The Center for the Study of Language and Information Publications