1. Terrain parameters directly from a digital terrain model;Collins;Canadian Surveyor,1975
2. Algorithms for dense grid digital terrain models;Collins;Photogrammetric Engineering and Remote Sensing,1981
3. Criteria for constructing optimal digital terrain models;Craig,1983
4. General geomorphometry, derivatives of altitude and descriptive statistics;Evans,1972
5. An integrated system of terrain analysis and slope mapping;Evans,1980