1. An Analytical Study of Rock Penetration by a Single Bit Tooth;Cheatham,1958
2. An experimental study of a single-bit tooth penetration into dry rock at confining pressures of 0–5000 psi;Gnirk;Trans. Am. Inst. Mech. Engrs,1965
3. The effect of some drilling variables on the instantaneous rate of penetration;Outmans;Trans. Am. Inst. Mech. Engrs,1960
4. The theory of wedge indentation on ductile materials;Hill,1947
5. A preliminary model for wedge penetration in brittle materials;Paul;Trans. Am. Inst. Mech. Engrs,1965