Penny, E. M. (1932). The co-operative movement and the consumer. York: National Guild of Co-operators (NGC).
Cita Chicago (17th ed.)Penny, Edna M. The Co-operative Movement and the Consumer. York: National Guild of Co-operators (NGC), 1932.
Cita MLA (8th ed.)Penny, Edna M. The Co-operative Movement and the Consumer. York: National Guild of Co-operators (NGC), 1932.
Atenció: Aquestes cites poden no estar 100% correctes.