Zheng Zhang and  Xin Chen and  Guoqing Ding,  The System for Root Canal Length Measurement Based on Multifrequency Impedance Method.   journal   = {International Journal of Materials and Metallurgical Engineering}, [online]. World Academy of Science, Engineering and Technology.
    October 2018, vol. 143(11). 624 - 628
    [viewed 26 April 2024]. Available from: https://publications.waset.org/pdf/10009812.