by Metcheva, Roumiana, Beltcheva, Michaela, Naumov, Borislav, Yankov, Yordan, Michev, Tanyo, Profirov, Lyubomir, Mitov, Plamen, Kenderov, Lyubomir, Georgieva, Elena, Petrov, Petar, Goranov, Stoyan
Published in Geographical phorum (30.12.2016)