TY  - BOOK
AU  - Veldman,Wim
TI  - On sets enclosed between a set and its double complement
T2  - Report 9634
AV  - MATH QA3.R46 no.9634 
PY  - 1996///
CY  - Nijmegen
PB  - Department of Mathematics Catholic University
KW  - Set theory
KW  - Ordered sets
N1  - Includes bibliographical references
ER  -