Doryń, W. and Wawrzyniak, D. 2024. Heterogeneity in Air Pollution Levels and Their Techno‑economic Determinants: A Cluster Analysis of the EU–27. Comparative Economic Research. Central and Eastern Europe. 27, 3 (Sep. 2024), 47–66. DOI:https://doi.org/10.18778/1508-2008.27.21.