1. The Geometry of Involute Gears;Colbourne,1987
2. Gear Geometry and Applied Theory;Litvin,2004
3. Reference Book in Geometric Calculation of Involute and Worm Gearings;Bolotovskii,1986
4. Cylindrical Involute Gears and Gear Pairs — Concepts and Geometry,2007
5. GOST 16532–70, Cylindrical Involute External Gear Pairs — Calculation of Geometry, Moscow, Russia, 1970.