A three-item Likert-type scale designed to measure a person's proficiency with the use of a language, most likely a language other than the one the person is most familiar with.
Ahn, Jungsun and Carrie La Ferle (2008), “Enhancing Recall and Recognition for Brand Names and Body Copy: A Mixed-Language Approach,” Journal of Advertising, 37 (3), 107-117.
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