Valderrama, H. A. Financial condition and reporting practices of the GSIS. Philippine Management Review.
Chicago-referens (17:e uppl.)Valderrama, Helena Agnes. "Financial Condition and Reporting Practices of the GSIS." Philippine Management Review .
MLA-referens (9:e uppl.)Valderrama, Helena Agnes. "Financial Condition and Reporting Practices of the GSIS." Philippine Management Review, .
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