Finkle, J. (1998). Viagra heats up war among firms promising cure for impotence. Manila Times.
Chicago-viite (17. p.)Finkle, Jim. "Viagra Heats Up War Among Firms Promising Cure for Impotence." Manila Times 1998.
MLA-viite (9. p.)Finkle, Jim. "Viagra Heats Up War Among Firms Promising Cure for Impotence." Manila Times, 1998.
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