Contour Line and Geographic Feature Extraction from USGS Color Topographical Paper Maps.

Alireza Khotanzad Edmund Zink Contour Line and Geographic Feature Extraction from USGS Color Topographical Paper Maps. 18-31 2003 25 IEEE Trans. Pattern Anal. Mach. Intell. 1 http://computer.org/tpami/tp2003/i0018abs.htm db/journals/pami/pami25.html#KhotanzadZ03