Não informado. (1956). Review of the Polish Academy of Sciences. Polish Academy of Sciences.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रNão informado. Review of the Polish Academy of Sciences. Warsaw: Polish Academy of Sciences, 1956.
एमएलए (8वां संस्करण) प्रशस्ति पत्रNão informado. Review of the Polish Academy of Sciences. Polish Academy of Sciences, 1956.
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