1. Abiteboul, S., Hull, R., Vianu, V.: Foundations of Databases. Addison-Wesley, Reading (1995)
2. Ackermann, W.: Zur Axiomatik der Mengenlehre. Math. Ann. 131, 336–345 (1956)
3. Aczel, P.: Non-Well-Founded Sets. CSLI Lecture Notes 14, Center for the Study of Language and Information. Stanford Univ. (1988)
4. Studies in Logic and the Foundations of Mathematics;H. Barendregt,1984
5. Barendregt, H.: The impact of the lambda calculus in logic and computer science. Bull. Symbolic Logic 3, 181–215 (1997)