1. Maier, M., Porinelli, R.: Separating Graphic Objects in Written Texts. Advances in Image Processing and Pattern Recognition (1986)
2. Kasturi, R., Bow, S., El-Masri, W., Shah, J., Gattiker, J., Mokate, U.: A System for Interpretetion of Line Drawings, Vol. 12. IEEE Trans. On Patt. Anal. And Mach. Intell., (1990) 978–991
3. Verikas, A., Bachauskene, M., Vilunas, S., Skaisgiris, D.: Adaptive Character Recognition System, Vol. 13. Pattern Recognition Letters, (1992) 207–212
4. Lettera, Maier, M., Paoli, C.: Character Recognition in Office Automation, Advances in Image Processing and Pattern Recognition, eds V. Cappellini and R. Marconi, Elsvier Science Publishers B. V., North-Holland, (1986) 191–197