Cita APA (7th ed.)

Santos, B., & Manzano, R. G. (2009). Principles of tourism 1. C & E Pub.

Cita Chicago (17th ed.)

Santos, Buen, i Ronald G. Manzano. Principles of Tourism 1. Quezon City: C & E Pub, 2009.

Cita MLA (9th ed.)

Santos, Buen, i Ronald G. Manzano. Principles of Tourism 1. C & E Pub, 2009.