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Chicago-viite (17. p.)Sadongdong, Martin A. "PH Defeats 'Delta': 2M More Pfizer Jabs Arriving Next Week." Manila Bulletin 2021.
MLA-viite (9. p.)Sadongdong, Martin A. "PH Defeats 'Delta': 2M More Pfizer Jabs Arriving Next Week." Manila Bulletin, 2021.
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