Casayuran, M. B. Filipinos becoming largely environmentally conscious. Manila Bulletin.
Chicago-viite (17. p.)Casayuran, Mario B. "Filipinos Becoming Largely Environmentally Conscious." Manila Bulletin .
MLA-viite (9. p.)Casayuran, Mario B. "Filipinos Becoming Largely Environmentally Conscious." Manila Bulletin, .
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