Hack-Handa, József, Zoltán Veres, and Éva Nádor. 2019. “Secrets of Successful Project Relationships: Perceived Project Competencies of Sellers and Buyers”. The Hungarian Journal of Marketing and Management 46 (3):55-63. https://journals.lib.pte.hu.testing.qulto.eu/index.php/mm/article/view/387.