Παραπομπή APA

Hogan, P. (1974). Playgrounds for free: The utilization of used and surples materials in playground construction. MIT press.

Παραπομπή Chicago Style

Hogan, Paul. Playgrounds for Free: The Utilization of Used and Surples Materials in Playground Construction. Cambridge: MIT press, 1974.

Παραπομπή MLA

Hogan, Paul. Playgrounds for Free: The Utilization of Used and Surples Materials in Playground Construction. MIT press, 1974.