1. Rominger, G.S. (1893). Worm. Gear. Cutting Machine. (405,030), U.S. Patent.
2. Baerbalck, H., Hamilton, O.H., and Carr, R.S. (1907). Relieving Mechanism for Engine Lathes. (870,759), U.S. Patent.
3. Fellows, L.E.R. (1890). Machine for Grinding Gear Generating Cutters. (686,599), U.S. Patent, (Application filed 24 June 1899).
4. (2024, March 01). Verified Market Reports. Available online: https://www.verifiedmarketreports.com/product/gear-manufacturing-market/.
5. Boral, P., Gołębski, R., and Kralikova, R. (2023). Technological aspects of manufacturing and control of gears—Review. Materials, 16.