WASET
    Robert S. Giachetti and  Emanuele Grossi,  Brief Review of the Self-Tightening, Left-Handed Thread.   journal   = {International Journal of Mechanical and Mechatronics Engineering}, [online]. World Academy of Science, Engineering and Technology.
    March 2021, vol. 172(4). 175 - 179
    [viewed 26 April 2024]. Available from: https://publications.waset.org/pdf/10011942.