Verhoeven, L., & Jong, J. H. A. L. d. (1992). The construct of language proficiency: Applications of psychological models to language assessment. John Benjamins.
Lua i Stíl Chicago (17ú heag.)Verhoeven, Ludo, agus John H. A. L. de Jong. The Construct of Language Proficiency: Applications of Psychological Models to Language Assessment. Amsterdam: John Benjamins, 1992.
Lua MLA (9ú heag.)Verhoeven, Ludo, agus John H. A. L. de Jong. The Construct of Language Proficiency: Applications of Psychological Models to Language Assessment. John Benjamins, 1992.
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