Gaya APA

(ETC), E, T, C., (UNWTO), W, T, O. (2011). Handbook on Tourism Product Development ( hanya tersedia file pdf ) . Spanyol: World Tourism Organization.

Gaya MLA

(ETC), European, Travel, Commission., (UNWTO), World, Tourism, Organization. "Handbook on Tourism Product Development ( hanya tersedia file pdf )". Spanyol: World Tourism Organization, 2011. Text.