1. Schantz HF (1982) History of OCR, optical character recognition. Recognition Technologies Users Association, Manchester Center, Vt., USA
2. Rabinow J (1969) Whither OCR? And whence? Datamation 15(7):38–42
3. Mori S, Suen CY, Yamamoto K (1992) Historical review of OCR research and development. Proc IEEE 80(7):1029–1058
4. Nagy G (1992) At the frontiers of OCR. Proc IEEE 80(7):1093–1100
5. Mori S, Nishida H, Yamada H (1999) Optical character recognition. Wiley, New York