Tirona, G. A. (1998). The family corporation: A new breeding ground for gurus. Philippine Star.
Chicago Style aipamenaTirona, Gertie Ampil. "The Family Corporation: A New Breeding Ground for Gurus." Philippine Star 1998.
MLA aipamenaTirona, Gertie Ampil. "The Family Corporation: A New Breeding Ground for Gurus." Philippine Star, 1998.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.