Cambridge Assessment English: http://www.cambridgeenglish.org/gr/

Common European Framework of Reference for Languages: Learning, Teaching, Assessment (CEFR): https://www.coe.int/en/web/common-european-framework-reference-languages/?

Hellenic American Union: http://www.hau.gr/

Goethe Institut: https://www.goethe.de/ins/gr/el/index.html

Università per Stranieri di Perugia: https://www.unistrapg.it/

UCAS: https://www.ucas.com/

COMPUTER ACADEMY: http://www.computeracademy.gr

https://http://www.aristontest.com