Katigbak, A. F. (2003). Almost 80 percent of Pfizer's sildenafil users prefer not to take other ED medications. Philippine Star.
Chicago Style (17th ed.) CitationKatigbak, Antonio F. "Almost 80 Percent of Pfizer's Sildenafil Users Prefer Not to Take Other ED Medications." Philippine Star 2003.
MLA (9th ed.) CitationKatigbak, Antonio F. "Almost 80 Percent of Pfizer's Sildenafil Users Prefer Not to Take Other ED Medications." Philippine Star, 2003.
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