Kazarin, O. B., Kazarin, B. O., Husiev, D. Y., Pastushkov, H. P., Pastushkov V. Г. and Zhykharev, D. V. (2008) “The practice of using GPR technology in the examination tunnel”, Science and Transport Progress , (21), pp. 113–116. doi: 10.15802/stp2008/16294.