Calimag, M. G. (2009). Contractor says GSIS may be at fault for its current IT system woes. Manila Bulletin.
Chicago-viite (17. p.)Calimag, Melvin G. "Contractor Says GSIS May Be at Fault for Its Current IT System Woes." Manila Bulletin 2009.
MLA-viite (9. p.)Calimag, Melvin G. "Contractor Says GSIS May Be at Fault for Its Current IT System Woes." Manila Bulletin, 2009.
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