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Lua i Stíl Chicago (17ú heag.)"GSIS Earns P25.8 B in 2001." Philippine Star 2002.
Lua MLA (9ú heag.)"GSIS Earns P25.8 B in 2001." Philippine Star, 2002.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.