TY  - BOOK
AU  - Gorr Wilpen L.
AU  -  Kurland Kristen S.
TI  - Learning and using geographic information systems
SN  - 9788131507605
U1  - U:(D6,9(B), P9 
PY  - 2004///
CY  -  New Delhi 
PB  - Cenage Learning        
ER  -