Orbeta, J., Orbeta, J. C. A., & Franco, B. V. J. (2001). Sec. Richard Gordon: 'Tourism is a sacred duty'. Kabayan.
Lua i Stíl Chicago (17ú heag.)Orbeta, Joseph, Joseph Christian A. Orbeta, agus Bernardo V. Jr Franco. "Sec. Richard Gordon: 'Tourism Is a Sacred Duty'." Kabayan 2001.
Lua MLA (9ú heag.)Orbeta, Joseph, et al. "Sec. Richard Gordon: 'Tourism Is a Sacred Duty'." Kabayan, 2001.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.