HMELO-SILVER, CINDY E., LEI LIU, and REBECCA JORDAN. 2009. “VISUAL REPRESENTATION OF A MULTIDIMENSIONAL CODING SCHEME FOR UNDERSTANDING TECHNOLOGY-MEDIATED LEARNING ABOUT COMPLEX NATURAL SYSTEMS”. Research and Practice in Technology Enhanced Learning 4 (3):253-80. https://rptel.apsce.net/index.php/RPTEL/article/view/2009-04010.