TY  - BOOK
TI  - Principles of Geographic Information Systems : : an introductory textbook / 
T2  - ITC educational textbook series, 
SN  - 9061641845
SN  - 1567-5777
U1  - 526.9 
PY  - 2000///
CY  - Enschede, Netherlands : 
PB  - International Institute for Aerospace Survey and Earth Sciences, 
KW  - Sistemas de informação geográfica
ER  -