Valentine, Stephanie, Francisco Vides, George Lucchese, David Turner, Hong-hoe Kim, Wenzhe Li, Julie Linsey, and Tracy Hammond. “Mechanix: A Sketch-Based Tutoring and Grading System for Free-Body Diagrams”. AI Magazine 34, no. 1 (December 6, 2012): 55. Accessed March 28, 2024. https://ojs.aaai.org/aimagazine/index.php/aimagazine/article/view/2437.