Villaviray, J. (2002). PPA based on capital investment says Viray. Manila Times.
Chicago-referens (17:e uppl.)Villaviray, Johnna. "PPA Based on Capital Investment Says Viray." Manila Times 2002.
MLA-referens (9:e uppl.)Villaviray, Johnna. "PPA Based on Capital Investment Says Viray." Manila Times, 2002.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.