Gaya APA
Twist, C.
(1997).
Macmillan Encyclopedia of Science jilid 7: The Environment
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Bandung:
Gunung Mulia.
Gaya MLA
Twist, Clint.
"Macmillan Encyclopedia of Science jilid 7: The Environment".
Bandung:
Gunung Mulia,
1997.
Referensi.