Bibliography

Bibliography

All the information came from the following sources: -

1) Young Children's Britannica

2) Internet :

encarta.msn.com

www.gov.sg/env/

www.osto.sintef.no/gemini/1994

www.msd.st-louis.mo.us/sss.html

3) World Book multimedia encyclopaedia

4) Hutchinson's encyclopaedia of science in everyday life

5) The Award Children's Encyclopaedia

6) Understanding Geography 1 page 109-111