Pavlova, Elitsa L. http://orcid.org/0000-0001-5708-3482
Toshkovska, Radostina D.
Doncheva, Tsvetelina E.
Ivanova, Iliana A.
Funding for this research was provided by:
Sofia University “St Kliment Ohridski”, Bulgaria (80-10-224/15.05.2019)
Ministry of Education and Science, Bulgaria (BG05M2OP001-1.002-0019)
Article History
Received: 29 March 2020
Revised: 15 April 2020
Accepted: 11 May 2020
First Online: 24 May 2020
Compliance with ethical standards
:
: All the authors declare no conflict of interest.