Cita APA (7a ed.)

Barnum, D. T. (1970). The Negro in the Bituminous Coal Mining Industry. Industrial Research Unit, Wharton School of Finance and Commerce, University of Pennsylvania; distributed by University of Pennsylvania Press.

Cita Chicago Style (17a ed.)

Barnum, Darold T. The Negro in the Bituminous Coal Mining Industry. Philadelphia: Industrial Research Unit, Wharton School of Finance and Commerce, University of Pennsylvania; distributed by University of Pennsylvania Press, 1970.

Cita MLA (8a ed.)

Barnum, Darold T. The Negro in the Bituminous Coal Mining Industry. Industrial Research Unit, Wharton School of Finance and Commerce, University of Pennsylvania; distributed by University of Pennsylvania Press, 1970.