TY  - BOOK
AU  - Bernhardsen Tor
TI  - Geographic information systems :  An introduction   
SN  - 0471321923
U1  - U:(D6,9(B), N9 
PY  - 1999///
CY  - New York
PB  - John Wiley        
KW  - Geography irt Computer Science
N1  - Bibliography: P 362-64
ER  -