Georgiev, Venelin. ??????? ? ???????, ???????? ? ?????????? ??????????? ?? ?????????? ?? ???????? ?? ?????????????? ??????????? ?? ??????????? ???? ?? ????????? ???????? 2032 In CSDM Views., 2021.

???????, ??????. ?????????? ?? ?????????? ?? ???????????? ??????????? In ?????????? ?? ??????????? ? ?????????. Vol. 8. ?????: ??????, 2020.

Ratchev, Valeri. ????????? ?????? ?? ??????????? ?? ????????? 2014: ????? ????? ? ????? ??????????? ????? In CSDM Views. ?????: ?????? ?? ?????????? ?? ??????????? ? ?????????, 2015.

Tagarev, Todor, Assya Davidova, and Anton Lazarov. ?????? ?? ???????? ?? ?????????????? ???????? ?? ????????? ???????? In CSDM Views. ?????: ?????? ?? ?????????? ?? ??????????? ? ?????????, 2013.

Tagarev, Todor, Assya Davidova, Anton Lazarov, and Rossen Ivanov. ????? ?? ????????? ?? ?????????????? ?? ????????? ?? ??????? ?? ?????????? ?? ?????????? ????????????, 13 ???? ? 28 ??? 2013 ?. In CSDM Views. ?????: ?????? ?? ?????????? ?? ??????????? ? ?????????, 2013.