The authors describe a pen-based modeling system for the styling design of 3D objects. Their system is tailored toward the rapid and intuitive design of styling features such as freeform curves and surfaces. Basic wireframe and surfaces are constructed and modified using the strategy of curve creation, curve modification, surface creation, and finally surface modification.
Levent Burak Kara, Kenji Shimada. (2007). Sketch-Based 3D Shape Creation for Industrial Styling Design. IEEE Computer Graphics and Applications, Volume 27, Number 1, Pages 60-71.