Н. Величков, „Dynamics and Macroeconomic Interaction of Government Expenditure in BELL and PIIGS: A Comparative Analysis“, НТ, бр. 4, стр. 119–128, Окт 2021, отворен на: Юли 22, 2026. достъпен на: https://bjiep.e-dnrs.org/index.php/rp/article/view/5263