1. Plaxis—Finite Element Code for Soils and Rock Plasticity, Version 3,1990
2. Nisa II—User's manual, Version 91.0,1991
3. Advanced Soil Mechanics;Das,1990
4. The universal earthmoving equation applied to chisel plough wings;Fielke;Journal of Terramechanics,1991
5. Interactions of the cutting edge of tillage implements with soil;Fielke,1994