Axarlis, Nikos (March 1998). "Tunnel Canceled". Archaeology. Long Island City: Archaeological Institute of America. Archived from the original on 11 November 2022. Retrieved 11 November 2022.
Skayannis, Pantoleon; Kaparos, George; et al. (February 2010). "Project Profile: Greece: Athens Metro (Attiko Metro)"(PDF). Bartlett School of Planning: Omega Centre. London: University College London. Archived from the original(PDF) on 6 November 2022. Retrieved 6 November 2022.
Skayannis, Pantoleon; Kaparos, George; et al. (February 2010). "Project Profile: Greece: Athens Metro (Attiko Metro)"(PDF). Bartlett School of Planning: Omega Centre. London: University College London. Archived from the original(PDF) on 6 November 2022. Retrieved 6 November 2022.
Axarlis, Nikos (March 1998). "Tunnel Canceled". Archaeology. Long Island City: Archaeological Institute of America. Archived from the original on 11 November 2022. Retrieved 11 November 2022.