Estrada, E. (2003). Quadruplets born ; 3 die after hospital runaround. Manila Times.
Chicago-viite (17. p.)Estrada, Eric. "Quadruplets Born ; 3 Die After Hospital Runaround." Manila Times 2003.
MLA-viite (9. p.)Estrada, Eric. "Quadruplets Born ; 3 Die After Hospital Runaround." Manila Times, 2003.
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