Научни трудове на УНСС = The Scientific Papers of UNWE129227 (ISSN : 0861-9344, EISSN : 2534-8957)Published by Sofiâ: Universitet za Nacionalno i Svetovno Stopanstvohttp://unwe-research-papers.org/enSHERPA/RoMEOVoir les documents associés Exporter Export XML Export RDF