- Athens International Airport, https://www.aia.gr/en/traveler/
- Athens Urban Transport Organisation S.A., http://www.oasa.gr/?lang=en
- Attiki Odos, http://en.aodos.gr/
- Attiko Metro S.A., http://www.ametro.gr/page/default.asp?id=4&la=2
- Egnatia Odos, http://www.egnatia.eu/page/default.asp?id=5&la=2
- Greek National Tourism Organisation, http://www.gnto.gov.gr/en
- Hellenic Center for Disease Control & Prevention, http://www.keelpno.gr/en-us/home.aspx
- Public Properties Company S.A., http://www.etasa.gr/
- Rio–Antirio bridge, http://www.gefyra.gr/en/
