Haralampiev, Kaloyan, and Dimitar Blagoev. “ETHNIC-SPECIFIC AND ETHNIC-NONSPECIFIC FACTORS FOR ETHNICITY NON-IDENTIFICATION IN BULGARIA”. Vanguard Scientific Instruments in Management 13 (December 10, 2017): 5-15. Accessed September 13, 2024. https://vsim-journal.info/index.php?journal=vsim&page=article&op=view&path[]=167.