Tomoko Fukuyama and  Osamu Senbu,  Nondestructive Electrochemical Testing Method for Prestressed Concrete Structures.   journal   = {International Journal of Civil and Environmental Engineering}, [online]. World Academy of Science, Engineering and Technology.
    February 2018, vol. 135(3). 336 - 340
    [viewed 05 August 2020]. Available from: https://publications.waset.org/pdf/10008779.