APA (7th ed.) Citation

Sopkin, C. D. (1973). A comparison of social interaction within a structured activity environment and an unstructured activity environment. [publisher not identified].

Chicago Style (17th ed.) Citation

Sopkin, Charles David. A Comparison of Social Interaction Within a Structured Activity Environment and an Unstructured Activity Environment. [Place of publication not identified]: [publisher not identified], 1973.

MLA (9th ed.) Citation

Sopkin, Charles David. A Comparison of Social Interaction Within a Structured Activity Environment and an Unstructured Activity Environment. [publisher not identified], 1973.

Warning: These citations may not always be 100% accurate.