1. The Structure of Locally Compact Abelian Groups, Monographs and Textbooks in Pure and Applied Mathematics Vol. 68 (Marcel Dekker, Inc., New York, 1981).
2. Answer to Raczkowski's questions on convergent sequences of integers
3. Filters in Number Theory and Combinatorics, Ph. D. thesis (Technische Universität Wien, Wien, October 2004).