TY  - BOOK
AU  - Wadsworth,Richard
AU  - Treweek,Jo
TI  - GIS for ecology: an introduction 
SN  - 0582246520
PY  - 1999///
CY  - New York
PB  - Longman
KW  - Ecology
KW  - Data processing
KW  - Geographic information systems
N1  - References : p. 172-176
ER  -