1. Issues and challenges in combining SLA research and language testing;Alanen,2012
2. Investigating variability in tasks and rater judgements in a performance test of foreign language speaking;Bachman;Language Testing,1995
3. Fitting linear mixed-effects models using lme4;Bates;Journal of Statistical Software,2015
4. Describing language development? Rating scales and SLA;Brindley,1998
5. Bundesinstitut für Bildungsforschung Innovation & Entwicklung des österreichischen Schulwesens. (2014). Assessment scale B2 and guidelines. Vienna, Austria. Retrieved from https://www.srdp.at/downloads/?tx_solr%5Bfilter%5D%5B1%5D=subject%253A%252FLebende%2BFremdsprachen&tx_solr%5Bfilter%5D%5B0%5D=documentType%253A%252FBegleitmaterialien%252FRichtlinien%252C%2BKonzepte%2B%2526%2BModelle.