Author:
Kachakova Darina,Stoyanov Orlin,Dzhebir Gyulnas,Todorov Spiridon,Varbanova Sonia,Popov Todor,Dobriyanova Venera,Marinov Tzvetomir,Mitev Vanio,Popova Diana,Kaneva Radka
Publisher
"Prof. Marin Drinov" Publishing House of Bulgarian Academy of Sciences