TY - BOOK AU - Gelbaum, Bernard R., AU - Olmsted, John M. H, TI - Theorems and counterexamples in mathematics T2 - Problem books in mathematics SN - 9788184895438 U1 - 510 GEL PY - 1990/// CY - New York PB - Springer-Verlag KW - Mathematics N1 - Includes index ER -