Author: Doytcho Dimov, Atanas Vuchkov
population
3. State of popolation Goniolimon collinum (Griseb.) Boiss. in locality Yazovira
Author: Ivanka Ivanova, Nadejda Zaprianova, Valeria Ivanova
5. A demographic look at the municipality of Plovdiv over the 2008-2013 period
Author: Atanas Kounchev, Zhenja Hristova, Petar Marinov