Cruz, Z. L. (2013). Principles of tourism. Rex Book Store.
Chicago Style aipamenaCruz, Zenaida Lansangan. Principles of Tourism. Manila: Rex Book Store, 2013.
MLA aipamenaCruz, Zenaida Lansangan. Principles of Tourism. Rex Book Store, 2013.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.