Cita APA (7a ed.)

North, B. (2000). The development of a common framework scale of language proficiency. Peter Lang.

Cita Chicago Style (17a ed.)

North, Brian. The Development of a Common Framework Scale of Language Proficiency. New York: Peter Lang, 2000.

Cita MLA (9a ed.)

North, Brian. The Development of a Common Framework Scale of Language Proficiency. Peter Lang, 2000.