Não informado. (2020). Abstracts of Bulgarian Scientific Literature. Agricultural Academy, Center for Scientific, Technic and Economic Information.
Chicago-viite (17. p.)Não informado. Abstracts of Bulgarian Scientific Literature. Sofia: Agricultural Academy, Center for Scientific, Technic and Economic Information, 2020.
MLA-viite (8. p.)Não informado. Abstracts of Bulgarian Scientific Literature. Agricultural Academy, Center for Scientific, Technic and Economic Information, 2020.
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