Government Service Insurance System (GSIS). (2011). GSIS art competition: 2011. [Government Service Insurance System].
Chicago-viite (17. p.)Government Service Insurance System (GSIS). GSIS Art Competition: 2011. [Pasay City]: [Government Service Insurance System], 2011.
MLA-viite (9. p.)Government Service Insurance System (GSIS). GSIS Art Competition: 2011. [Government Service Insurance System], 2011.
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