Sofia, Sofia, Bulgaria
Serdica, Sofia City Province, Bulgaria
Sint-Niklaas, Flanders, Belgium
Rostov-on-Don, Rostov Oblast, Russian Federation
Popovo, Targovishte Province, Bulgaria
Varna, Varna, Bulgaria
Plovdiv, Plovdiv Province, Bulgaria
Sofia, Sofia City Province, Bulgaria
Kazanluk, Stara Zagora, Bulgaria
Leipzig, Sachsen, Germany