Cita APA (7th ed.)

Köpke, G., & Grundheber-Pilgram, A. (1990). The centenary of May Day ; Portrait of the European Trade Union Confederation (ETUC). Brussels: ETUI.

Cita Chicago (17th ed.)

Köpke, Günter, i Alfons Grundheber-Pilgram. The Centenary of May Day ; Portrait of the European Trade Union Confederation (ETUC). Brussels: ETUI, 1990.

Cita MLA (8th ed.)

Köpke, Günter, i Alfons Grundheber-Pilgram. The Centenary of May Day ; Portrait of the European Trade Union Confederation (ETUC). Brussels: ETUI, 1990.