Ikonomičeskite vrăzki na Bălgarija s razvivaštite se strani - Kamenov, Evgenij G. 1908- (Bălgarska Akad. na Naukite, 1970)
PT: Economic relations between Bulgaria and the developing countries. - In kyrill. Schr., bulg. - Zsfassung in engl. und russ. Sprache