Rotor, N. S. (1980). Introduction to Philippine tourism. Integrated Research Center, De La Salle University.
Chicago-viite (17. p.)Rotor, Nilda Servando. Introduction to Philippine Tourism. Manila: Integrated Research Center, De La Salle University, 1980.
MLA-viite (9. p.)Rotor, Nilda Servando. Introduction to Philippine Tourism. Integrated Research Center, De La Salle University, 1980.
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