TY  - BOOK
AU  - Ratzan,Lee
TI  - Understanding information systems: what they do and why we need them 
SN  - 9788184082388
PY  - 2009///
CY  - New Delhi
PB  - Indiana Publishing House
KW  - Information science
KW  - Information storage and retrieval systems
KW  - Computer science
KW  - Popular works
KW  - Mathematics
N1  - Includes bibliographical references (p. 237-245) and index
ER  -