References
- Ching , F.D. K. 1990 . Drawing: A Creative Process , New York : Van Nostrand Reinhold .
- Ching , F.D. K. 1996 . Architectural Graphics, , third edition , New York : Van Nostrand Reinhold .
- Porter , T. and Goodman , S. 1996 . Manual of Graphic Techniques , volume 4 , London : Butter‐worth .