TY  - BOOK
AU  - Canby, Thomas Y.
TI  - Our changing Earth
SN  - 0870449109
U1  - GR 363.7 C214 1994 
PY  - 1994///
CY  - Washington
PB  - National Geographic Society
KW  - Environmentalism
KW  - Environmental degradation- Citizen participation
KW  - Nature- Effect of human beings on
KW  - Conservation of natural resources
N1  - Includes index
ER  -