Espina, R. L. (2001). Hydrogen sulfide downs 36 students. IN The southern beat [column]. Philippine Star.
Chicago-viite (17. p.)Espina, Rolly L. "Hydrogen Sulfide Downs 36 Students. IN The Southern Beat [column]." Philippine Star 2001.
MLA-viite (9. p.)Espina, Rolly L. "Hydrogen Sulfide Downs 36 Students. IN The Southern Beat [column]." Philippine Star, 2001.
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