https://visegradinsight.eu/moderate-reactivation-weimar-triangle/
https://www.ips-journal.eu/index.php?id=340&L=0&tx_news_pi1[news]=3894&tx_news_pi1[controller]=News&tx_news_pi1[action]=detail&utm_source=newsletter&utm_medium=email&utm_campaign=en_725_20191126&cHash=ac2f2b518fa84d486b1e9d1776dad3dd
https://onlinelibrary.wiley.com/doi/epdf/10.1111/1467-923X.13172
https://wiiw.ac.at/the-berlin-process-for-the-western-balkans-four-recommendations-to-achieve-progress-n-582.html