Keller, N., & Swaney, D. (1998). Tonga (3rd ed.). Lonely Planet Pub.
Chicago Style aipamenaKeller, Nancy, and Deanna Swaney. Tonga. 3rd ed. Hawthorn, Vic., Australia: Lonely Planet Pub, 1998.
MLA aipamenaKeller, Nancy, and Deanna Swaney. Tonga. 3rd ed. Lonely Planet Pub, 1998.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.