Langit, R. B. (1997). Water from polluted rivers to be recycled for drinking. Manila Times.
Chicago Style aipamenaLangit, Richel B. "Water from Polluted Rivers to Be Recycled for Drinking." Manila Times 1997.
MLA aipamenaLangit, Richel B. "Water from Polluted Rivers to Be Recycled for Drinking." Manila Times, 1997.
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