Grzegorz Dziamski (1996). Od Awangardy Do Postmodernizmu. Instytut Kultury. ISBN83-85323-21-X, p. 192
Pańswowy Instytut Sztuki (1963). Studia z historii sztuki. Vol. 9-12, p. 7 (considered as first publication of the sculpture without any copyright notice)
La persona que ha associat un treball amb aquest document ha dedicat l'obra domini públic, renunciant en tot el món a tots els seus drets de d'autor i a tots els drets legals relacionats que tenia en l'obra, en la mesura permesa per la llei. Podeu copiar, modificar, distribuir i modificar l'obra, fins i tot amb fins comercials, tot sense demanar permís.
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