Authors
Volodymyr Levytskyi
Department of Mine Surveying Zhytomyr State Technological University St. Chudnivska 103, 10005,, Zhytomyr, Ukraine
© 2017 Volodymyr Levytskyi, published by Warsaw University of Technology
This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.