Παραπομπή APA

Cummins, E., & Devyver, F. T. (1947). Labour problem in the United States. N.van nustrand co.

Παραπομπή Chicago Style

Cummins, E.E, και Frank T. Devyver. Labour Problem in the United States. London: N.van nustrand co, 1947.

Παραπομπή MLA

Cummins, E.E, και Frank T. Devyver. Labour Problem in the United States. N.van nustrand co, 1947.