Não informado. (1981). Zbornik Radova Prirodno-Matematickog Fakulteta. University of Novi Sad, Institute of Mathematics, Faculty of Science.
Chicago-viite (17. p.)Não informado. Zbornik Radova Prirodno-Matematickog Fakulteta. Novi Sad, Iugoslavia: University of Novi Sad, Institute of Mathematics, Faculty of Science, 1981.
MLA-viite (8. p.)Não informado. Zbornik Radova Prirodno-Matematickog Fakulteta. University of Novi Sad, Institute of Mathematics, Faculty of Science, 1981.
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