V. D. Bravo Morocho, E. P. Abarca Pérez, S. A. López Ortíz, and J. J. Freire Bravo, “Manufacture of a head prototype of a 100 cc single cylinder two-stroke engine applying reverse engineering and the CAD / CAM method.”, CCD, vol. 4, no. 3.1, pp. 190-206, Aug. 2021.