Tönisson E, Lepp M. Students’ Comparison of Their Trigonometric Answers with the Answers of a Computer Algebra System in Terms of Equivalence and Correctness. R&E-SOURCE [Internet]. 27. Oktober 2014 [zitiert 27. April 2024];1. Verfügbar unter: https://journal.ph-noe.ac.at/index.php/resource/article/view/85