https://www.nzz.ch/meinung/russland-gegen-ukraine-putin-plant-einen-langen-krieg-ld.1772254
http://www.iemed.org/observatori/arees-danalisi/arxius-adjunts/anuari/med.2018/IEMed_Crisis_EU_project_Medyearbook2018_Marc_Pierini.pdf
http://www.pircenter.org/en/news/6973-1224507
https://www.iiss.org/publications/strategic-dossiers/iran-dossier/iran-19-03-ch-1-tehrans-strategic-intent