Não informado. (2020). Abstracts of Bulgarian Scientific Literature. Agricultural Academy, Center for Scientific, Technic and Economic Information.
Chicago-referens (17:e uppl.)Não informado. Abstracts of Bulgarian Scientific Literature. Sofia: Agricultural Academy, Center for Scientific, Technic and Economic Information, 2020.
MLA-referens (8:e uppl.)Não informado. Abstracts of Bulgarian Scientific Literature. Agricultural Academy, Center for Scientific, Technic and Economic Information, 2020.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.