@misc{_Bulletin_1980, volume={28}, editor={Polska Akademia Nauk.}, editor={Państwowe Wydawnictwo Naukowe (1951–1992)}, copyright={Rights Reserved - Restricted Access}, address={Varsovie}, howpublished={online}, year={1980}, publisher={Państwowe Wydawnictwo Naukowe}, language={eng, fre, rus}, type={Text}, title={Bulletin de lʾAcademie Polonaise des Sciences. Série des Sciences Mathématiques T. 28 (1980)}, }