1. Recognition of handwritten numerical characters for automatic letter sorting;Genchi,1968
2. Syntax-directed interpretation of classes of pictures;Narisimhan;Comm. ACM,1966
3. A transformation for extracting new descriptors of shape, models for the perception of speech and visual form;Blum,1967
4. Distance functions on digital pictures;Rosenfeld;Pattern Recognition,1968
5. Computer representation of planar regions by their skeletons;Rosenfeld;Comm. ACM,1967