Citazione APA

Butler, G. D. (1936). Playgrounds, their administration and operation: National recreation association. A.S. Barnes.

Stile di citazione Chicago

Butler, George D. Playgrounds, Their Administration and Operation: National Recreation Association. New York: A.S. Barnes, 1936.

Citazione MLA

Butler, George D. Playgrounds, Their Administration and Operation: National Recreation Association. A.S. Barnes, 1936.

Attenzione: Queste citazioni potrebbero non essere precise al 100%.