1. K. Chhabra: Graphic symbol recognition: an overview. Proc. GREC’97, Nancy, France (1997) 244–252
2. D Blostein: General diagram recognition methodologies. Proc. GREC’95, University Park, PA (1995) 200–212
3. K. Tombre: Analysis of engineering drawings: state of the art and challenges. Proc. GREC’97 (1997) 54–61
4. J. F. Arias and R. Kasturi: Recognition of Graphical Objects for Intelligent Interpretation of Line Drawings, in Aspects of visual form processing. C. Arcelli, L. P. Cordella and G. Sanniti di Baja Eds, World Scientific (1994) 11–31
5. Lect Notes Comput Sci;L. O. Gorman,1996