Ma, C., Qin, S., Wang, H., & Dai, G. (2010). Modeling Sketching Primitives to Support Freehand Drawing Based on Context Awareness. Computing and Informatics, 29(4), 585–600. https://cai.type.sk/content/2010/4/modeling-sketching-primitives-to-support-freehand-drawing-based-on-context-awareness/