1. Engineering Tribology (Chapter 7);Williams,1994
2. Lubrication of Gear Teeth;Martin;Eng. Lond.,1916
3. Contact Mechanics (Chapter 4);Johnson,1985
4. Elasto-hydrodynamic Lubrication;Dowson,1977
5. Lubrication characteristics of involute spur gears;Gatcombe;Trans. ASME,1945