1. Allmaras, R.R., Burwell, R.E., Larson, W.E., Holt, R.F., 1966. Total porosity and random roughness of the interrow zone as influenced by tillage. USDA, Conservation Research Report no. 7, 22 pp
2. Anon, 1975. Soil Taxonomy. A basic system for soil classification for making and interpreting soil surveys. USDA Agricultural Handbook no. 436, US Government Press, Washington, DC
3. A field measurements of total porosity and surface microrelief of soils;Burwell;Soil Sci. Soc. Am. Proc.,1963
4. Infiltration as influenced by tillage-induced random roughness and pore space;Burwell;Soil Sci. Soc. Am. Proc.,1969
5. The analysis of soil surface roughness;Currence;Trans. ASAE.,1970