Bollen L, Gijlers H, van Joolingen W. Drawings in Computer-Supported Collaborative Learning - Empirical and Technical Results. Comput. Inform. [Internet]. 2015 Oct. 24 [cited 2024 May 2];34(3):559-87. Available from: https://www.cai.sk/ojs/index.php/cai/article/view/3221