Παραπομπή σε μορφή APA (7η εκδ.)

Machlis, G. E., & Tichnell, D. L. (1985). The state of the world's parks: An international assessment for resource management, policy, and research. Westview Press.

Παραπομπή σε μορφή Chicago (17η εκδ.)

Machlis, Gary E., και David L. Tichnell. The State of the World's Parks: An International Assessment for Resource Management, Policy, and Research. Boulder, Colo: Westview Press, 1985.

Παραπομπή σε μορφή MLA (9th εκδ.)

Machlis, Gary E., και David L. Tichnell. The State of the World's Parks: An International Assessment for Resource Management, Policy, and Research. Westview Press, 1985.